Sometimes the U.S. Navy says that its role is often to “kick in the door” – to gain access to places we want to influence, which do not want us. The U.S. Navy calls its efforts to bar the door “anti-access.” Three countries exemplify different approaches to barring the door: China, which is on the high-tech end; Iran, which relies on lower-tech mass; and Venezuela, which seems to use the supposed U.S. threat for domestic purposes, hence has spent only minimally on self-defense.

The second problem, which now seems to dominate, is the U.S. threat to intervene in a future cross-straits attack on Taiwan. Whether or not such an attack is planned, it is important to the Chinese government that Taiwan feels realistically threatened, because that, in turn, will bend the government on Taiwan to the will of those in Beijing. The Chinese view is apparently that the U.S. Navy, and particularly its carriers, could defeat any cross-straits invasion, so there is an emphasis on anti-carrier operations.

For China, the problem is twofold. One is the threat for which the Chinese navy was originally conceived (in the image of an earlier Soviet navy): attacks on the Chinese coast. To a very limited extent that was a realistic concern in the years after the Nationalists withdrew to Taiwan, and coastal forces were also a way to harass remaining Nationalist garrisons on offshore islands such as Quemoy and Matsu. The second problem, which now seems to dominate, is the U.S. threat to intervene in a future cross-straits attack on Taiwan. Whether or not such an attack is planned, it is important to the Chinese government that Taiwan feels realistically threatened, because that, in turn, will bend the government on Taiwan to the will of those in Beijing. The Chinese view is apparently that the U.S. Navy, and particularly its carriers, could defeat any cross-straits invasion, so there is an emphasis on anti-carrier operations. Such an emphasis would have been realistic in any case because the carriers are the main means by which the United States can project force against China on a sustained basis. Moreover, anything that can defeat the U.S. carrier force can also deal with other naval forces such as amphibious ships.

Chinese official policy is to define a series of offshore “island chains” defining boundaries within which its navy is to exercise sea control. This is the vision of an army rather than a navy. Sea control really means the ability to protect one’s own ships while destroying most enemy ones in the controlled area, but the sea is much too wide to allow the sort of control armies try to exercise. Navies just cannot be numerous enough. During the Cold War, the U.S. and Soviet navies learned how to conduct effective ocean surveillance as a means of cueing forces over wide ocean areas. The current Chinese navy was created by the Soviets, and presumably it learned the Soviet style of warfare. Although contact with the Soviets ended about 1960 with the Sino-Soviet split, the style probably survived. About 1960, the Soviets were creating an ocean denial (anti-carrier) capability based on a combination of submarines and missile-carrying bombers, all cued mainly by radio direction-finding stations ashore. Later Soviet naval development increased the range of the anti-carrier forces (some have said in response to longer-range U.S. naval aircraft) and used more sophisticated means of finding ships in the open sea, including satellites. They also became interested in over-the-horizon radar. The Soviets tried to add a component that would attack U.S. strategic submarines, but their attempts to develop a long-range submarine location system, analogous to the U.S. Sound Surveillance System (SOSUS), generally failed.

The core components of the Soviet system were its sensors and its ocean surveillance tracking center. It seems reasonable to imagine that a Chinese navy that began with Soviet ideas of naval strategy has followed a similar path. One mark of such a system is that ships or aircraft pop up near U.S. carrier forces without having searched for them (in the Soviet case, bombers started doing that in the early 1960s, prompting a search for the sensors cueing them). The tracking center is key because without it, the sensors register where the fast carriers were, but not where they are likely to go, hence cannot cue interceptors such as submarines. One indication that the Chinese may be following this path was the open-ocean interception of the carrier Kitty Hawk by a relatively slow Chinese diesel submarine a few years ago. The Chinese presumably obtained radio direction-finding technology from the Soviets before 1960 (for a time, the Russians wanted the Chinese to join a merged Pacific fleet, and to contribute intelligence to it). They may have gained later Russian technology after the Soviet collapse, when relations improved and the Russians seemed to be willing to sell almost any military technology, other than nuclear. The earlier connection with Soviet practices probably made it easier to assimilate the sort of long-range sensors the Soviets had conceived specifically for ocean surveillance.

ne indication that the Chinese may be following this path was the open-ocean interception of the carrier Kitty Hawk by a relatively slow Chinese diesel submarine a few years ago. The Chinese presumably obtained radio direction-finding technology from the Soviets before 1960 (for a time, the Russians wanted the Chinese to join a merged Pacific fleet, and to contribute intelligence to it).

There is direct evidence that the Chinese bought one particular sensor. For some years the Russians have advertised a relatively short-range over-the-horizon radar called Podsolnikh. It embodies a technology on offer from other countries: high-frequency surface wave radar. Such radar reaches out to about 180 nautical miles, exploiting the fact that the ground wave from a high-frequency transmitter carries that far. If such a radar is successful, it can almost certainly detect stealthy ships and airplanes, simply because its long pulses are not much affected by the subtleties of stealth shaping. The long pulses also limit the radar’s precision; it locates a target within a box a few miles on a side. Commercial satellite photographs show at least one such radar in a coastal position.

The Chinese bought (and later copied) the Russian Su-30 multi-role fighter aircraft, which they sometimes characterize as an anti-carrier missile carrier. They already have an anti-ship missile-carrying version of their copy of the old Soviet “Badger” (Tu-16), but the existing missile is not very impressive. If, as seems likely, the airplane uses analog electronics, modifying it for a better missile would not be a trivial proposition. The far more agile and much more modern Su-30 is different, and the Chinese probably see it as a kind of equivalent to the Backfire force which the U.S. Navy faced during the Cold War.

The Chinese are interested in convincing the U.S. government that the U.S. Navy’s carriers cannot survive anywhere near Taiwan. In combat the Su-30s might well be effective, but contemplating them the U.S. Navy is well aware that it has worked for years to defeat enemy air threats. Deterrence, at least in Chinese eyes, probably requires something a lot more impressive. The Chinese may believe they have just that in their new DF-21 missile, which has a maneuverable warhead. Chinese engineers have written that, given appropriate data, this kind of missile is difficult to intercept (because it maneuvers on the way down), and that its submunition warhead makes up for some inaccuracy in aiming. Although the submunitions could not destroy a carrier, presumably they could sweep its flight deck clear of aircraft, neutralizing it. Apparently the missile has been tested ashore, although exactly what that means is difficult to say. Containers supposedly carrying the missile were featured in the massive parade marking the 60th anniversary of the People’s Republic in 2009.

Just how effective DF-21 might be is a more difficult question. Much depends on how precise Chinese ocean surveillance is, or can be. Aircraft, like Su-30s, exploiting ocean surveillance data make up for the imprecision by using their own radars. That of course tips off the prospective target and also opens the attackers to deception and jamming. DF-21 has its own terminal sensor, but it is moving very fast, and presumably its scope for maneuver is somewhat limited. However tricky its terminal course, it is detectable as soon as it is fired (the United States has spent heavily to be certain of detecting missile launches as strategic warning). Yet another point is that the U.S. government might not realize that the missile being fired was a DF-21 aimed at a U.S. carrier; it might react as though the missile were a strategic weapon aimed at the United States. After all, Chinese generals have warned that the United States might find itself sacrificing Los Angeles, Calif., to save Taipei. The Chinese government may realize as much, because when the United States announced that it was planning to develop and deploy an instant non-nuclear strike system, presumably using ballistic missiles, the Chinese (and the Russians) said that such firings could trigger nuclear retaliation.

After all, Chinese generals have warned that the United States might find itself sacrificing Los Angeles, Calif., to save Taipei. The Chinese government may realize as much, because when the United States announced that it was planning to develop and deploy an instant non-nuclear strike system, presumably using ballistic missiles, the Chinese (and the Russians) said that such firings could trigger nuclear retaliation.

Of course, the Chinese have other weapons. If they can indeed detect and track carriers in the open ocean, then they can hope to cue submarines to attack. Although right now their nuclear submarine force is tiny, presumably it will grow in time. Again, as with the Su-30s, this force might be effective but it is unlikely to impress the U.S. government so deeply as to prevent the United States from thinking about intervening in a Straits crisis – which is what barring the door probably really means to the Chinese government.

For the Iranian government, the threat of naval attack, and particularly of invasion, is both real and a valuable means of mobilizing popular support. The great question, for a U.S. tactical planner, is how well the Iranians can track whatever is happening beyond the horizon in the Gulf. If they cannot do so, then all of their efforts to deny access to the United States cannot prevent us from maintaining a force in the Gulf and attacking over the horizon with airplanes, assault helicopters, and, probably, air cushion landing craft. Since they cannot mine or fortify their entire coast, if they cannot guess where we are, they cannot do much about our forces until we land.

Not surprisingly, the Iranians spend very little time talking about anything as boring as ocean surveillance. They emphasize their efforts to become self-sufficient in producing weapons such as anti-ship missiles and midget submarines. They also emphasize the spirit of their Iranian Revolutionary Guard Corps, which also happens to be the force standing between the regime and its public (and, probably, its regular armed forces). The idea is that spirit, manifested in heroes willing to engage “the Great Satan” aboard small motorboats and midget submarines, will somehow overcome U.S. technology, which is not backed by any true belief. Those who claim that suicide bombing is the decisive weapon that will crush the Western infidels say much the same thing. It happens that the Japanese said much the same thing during the run-up to World War II; somehow the indomitable Japanese spirit would overcome the wealth of the West. That did not quite work out.

The motorboats are intended to swarm around U.S. warships, damaging them despite high casualties. Their only real chance would come at the outset of a war, when normal rules of engagement preclude attacking boats that were not manifesting hostile intent. The Iranians undoubtedly find it encouraging that those aboard USS Cole could not fire at the approaching boat, which nearly sank the ship when it exploded: It was not obviously hostile. However, in a period of great tension, it seems likely that a U.S. naval force in the Gulf would try to set up an exclusion zone, and would sink anyone entering it. The unfortunate 1988 Vincennes incident suggests that U.S. naval officers faced by what looks like an Iranian attack might well be willing to shoot. Presumably they would be extremely aware of Iranian hostility during a period of tension. One point rarely made about the Vincennes incident is that the perceptions of the captain of the ship were shaped partly by emphatic Iranian claims that “the Great Satan” would be punished that weekend (which happened to be July 4th weekend, the right time to humiliate the Great Satan). It turned out that the Iranians were huffing and puffing to no particular end, but it seems that their rhetoric will likely justify what may look like pre-emptive action.

The Iranians undoubtedly find it encouraging that those aboard USS Cole could not fire at the approaching boat, which nearly sank the ship when it exploded: It was not obviously hostile. However, in a period of great tension, it seems likely that a U.S. naval force in the Gulf would try to set up an exclusion zone, and would sink anyone entering it.

Moreover, it is extremely unlikely that the Iranians can coordinate a mass strike by small boats manned by fervent but probably undisciplined operators against a dispersed naval force. Nor are the boats armed with weapons likely to sink a large ship at a single stroke. Thus there is every likelihood that the beginning of the attack would trigger counteraction by the mass of ships, with their boat-killing helicopters.

Iran has invested in coast-defense missiles. Although the Iranians claim that they are mass-producing a wide variety of such weapons, they appear to have been supplied by China or to have been produced under license. No credible estimate of numbers exists. Again, the question is whether such over-the-horizon weapons are linked to an over-the-horizon surveillance system. There must also be a question of quality control. The Iranian-supplied Chinese C802 missile fired at the Israeli corvette Hanit in 2006 caused only minimal damage, probably because it was fired ballistically and triggered as it passed overhead (a second missile did reportedly sink a merchant ship).

Iran also has a variety of more conventional anti-access weapons. They include a pair of Russian-supplied “Kilo”-class submarines, missile-firing attack boats, and Chinese-supplied rising mines. Again, a great deal depends on how well central command is exercised, which, in turn, is a question of how much Iranian attention – and resources – have gone into something other than the deterrent represented by the weapons themselves.

It is also not clear how well Iran is supplied with mines, and of what kind. During the war with Iraq, Iran tried to mine the Straits of Hormuz, the tanker route out of the Gulf, and the U.S. Navy captured and scuttled a minelayer loaded with what looked like old Russian-supplied contact mines. Before the fall of the Shah, the U.S. government regarded Iran as a close ally, and at one point, supposedly no conventional weapon was off the list the Shah could buy. This policy was reflected in the sale of the most sophisticated existing U.S. fighter, the F-14. It is not clear whether the Iranians received mines. If they did, they were probably kits to convert Mk. 80-series bombs into ground mines the U.S. Navy called Destructors. Aside from their individual effectiveness, Destructors offered the potential of huge numbers of mines without the cost of storage usually associated with these weapons. Nor is it clear how many mines (and of what kind) Iran obtained from China. Chinese mines for export include a controlled mine using acoustic signals. This kind of weapon is attractive because it can close off a denied area without necessarily threatening friendly shipping (on the other hand, an acoustic receiver submerged in warm water for any length of time may become quite unreliable). The rising mine the Iranians claim they have fires a rocket upward when it is triggered by the appropriate acoustic ship signature. The rocket does not maneuver, but more sophisticated rising mines fire torpedoes and homing rockets. These weapons may actually be easier to sweep than more conventional mines, because they must rely on well-defined signatures that can be simulated (they cannot use pressure signature, which is apparently impossible to simulate). The Russians have also advertised a wide variety of mines since the end of the Cold War, and they are also supplying weapons to Iran, particularly air defense missiles.

Then there is Venezuela. Hugo Chávez finds the United States a hugely useful threat, helping to justify his more dictatorial tendencies, and explaining away his economic problems. He clearly hoped, and hopes, that the Russians will find Venezuela so valuable an ally in the Western Hemisphere that they will sell him weaponry at reduced prices.

Then there is Venezuela. Hugo Chávez finds the United States a hugely useful threat, helping to justify his more dictatorial tendencies, and explaining away his economic problems. He clearly hoped, and hopes, that the Russians will find Venezuela so valuable an ally in the Western Hemisphere that they will sell him weaponry at reduced prices. Unfortunately the Russians now find themselves paying cash to their weapons manufacturers, and in any case their production base has declined sadly since the Cold War. Chávez must fund an ambitious social program (which is what keeps him in power) out of the same declining oil revenues with which he buys weapons. Thus deals announced with Russia often have gone nowhere, particularly for big-ticket items such as submarines. In 2007, Chávez announced plans for nine submarines, to make any invasion impossible. In September 2009, a contract for 100 main battle tanks was announced, with submarines possibly to follow. At the time, it was claimed that Venezuela had bought $4.4 billion in arms from Russia, including fighters, helicopters, and assault rifles. It is possible that submarines intended originally for sale to Venezuela were sold instead to Vietnam.

Before announcing the apparently abortive submarine deal with Russia, the Venezuelans had also contacted the Germans and the French to buy their current export submarines.

Venezuela did buy four missile-armed corvettes (eight missiles each) and four patrol boats from a Spanish builder, but they are hardly the stuff of a massive access-denial operation.

If, as seems to be the case, Chávez is much more interested in retaining power than in dealing with an unlikely U.S. attack, buying fighters and tanks makes far more sense than buying submarines. As a former army officer, Chávez undoubtedly sees his army not only as a guarantee of survival, but also as the force that can unseat him.

If, as seems to be the case, Chávez is much more interested in retaining power than in dealing with an unlikely U.S. attack, buying fighters and tanks makes far more sense than buying submarines. As a former army officer, Chávez undoubtedly sees his army not only as a guarantee of survival, but also as the force that can unseat him. The air force occupies a similar position. In coups, air forces sometimes deal the decisive blow by bombing, say, the presidential palace. Tanks are a useful way of convincing the population not to riot, although the old French light tanks of the Venezuelan army would probably be more useful in that role than the massive Russian tanks Venezuela is buying. Tanks and fighters are also a way of convincing neighboring states not to interfere. For Chávez, that is a reasonable issue, since he is supporting the FARC narco-terrorists Colombia is trying to wipe out with U.S. assistance (he describes them as freedom-fighting guerrillas). Venezuela currently provides the FARC with a sanctuary that is probably keeping it alive.

This article was first published in The Year in Defense: Naval Edition 2010.