It has become commonplace in recent years to compare the United States to Rome, Greece, even Egypt – how those mighty civilizations fell and where America may be emulating them.

But there is a far more relevant – and recent – example of an economic and military superpower that charted a path the United States seems determined to follow: Spain in the 16th and 17th centuries.

But while Christopher Columbus failed in his quest for a new, shorter route to the riches of the Orient, Spain pursued conquest of the New World to a degree its competitors never matched.

Spain was a relatively new nation that threw off the rule of a powerful foreign empire, then followed the dreams of a foreign visionary many thought was seeking the impossible. But while Christopher Columbus failed in his quest for a new, shorter route to the riches of the Orient, Spain pursued conquest of the New World to a degree its competitors never matched.

Seizing the “easy” riches of gold and silver that were exclusive to the territories they conquered, Spain quickly became the wealthiest nation in Europe, if not the world, claiming domain over the first truly global empire, encompassing much of North and South America, as well as parts of Africa and Asia. In territory, it was mankind’s fourth largest, behind the British, Mongol and Russian empires.

Spain gained all this because it was the first to the New World (the Vikings and other non-settlers notwithstanding). It accepted the risks of challenging the unknown, developed the sailing technologies and strength to stay ahead of its competitors and turned sea-faring into a recipe for global power.

Then…it crumbled.

Too much wealth and attention were spent on activities – mostly military – that failed to sustain the empire, too little on managing and expanding its colonies and finding new sources of wealth beyond Native American gold and silver. The greatest sources of mineral wealth – coal and oil, which were in vast supply in the old empire – did not come into play until after Spain had lost those lands.

Spain’s European competitors, envious of its success, copied many of the fundamentals. But its status as a global super power was Spain’s to lose. And lose it did.

And now…it is crumbling.

The American story has been significantly different, yet disturbingly similar. Our Columbus was German rocket scientist Wernher von Braun, our New World outer space, our “easy” riches the technologies and capabilities that grew from being the first (and still only) nation to set foot on the moon and having the most and best satellites and launch vehicles, including the space shuttle.

There is a strong argument to be made that America won the Cold War and became the planet’s only true super power because of our success as a space-faring nation.

And now…it is crumbling.

We abandoned the moon a generation and a half ago. Unless there is a major policy change soon – which seems increasingly unlikely – in little more than a year we will give up the ability to send our own citizens even to the low Earth orbit International Space Station. By the time we now expect to return to spaceflight – in 2014, at best, although recent reports say it could be a year or more later – in what amounts to an over-sized Apollo space capsule of the type we left behind four decades earlier, Russia and China will have become dominant in manned space.

Both, along with Japan and India, also have programs under way to send their own astronauts to the moon and establish permanent manned bases there, possibly before America is able to return. China and Russia also have set target dates for manned missions to Mars, which their Lunar bases will facilitate.

Frankly, the last, best hope for America in space lies not with the government, but with private industry and entrepreneurs. A half dozen companies are working on commercial manned spaceflight; one already has succeeded, launching the same vehicle and two-man crew on two suborbital flights within days of each other. Suborbital tourist flights could begin about the time the shuttle is mothballed.

Pushing that further to an orbital capability, much less missions to the moon or beyond, will be far more difficult – and expensive. It will happen, but, in all likelihood, government programs and money will hold the edge on such achievements for the foreseeable future. The question is: Which governments?

Today, Spain remains a proud and relatively prosperous nation, but it has never again come close to the wealth and power it claimed for less than 400 years.

Just as Spain watched England and France replace it on the world stage, so may America find itself on the sidelines of space, muttering of past glories while its competitors – old and new – conquer the New Frontier. And just as the true wealth contained within the Spanish Empire did not become apparent until it was lost, so too may be the true value of Lunar and Martian colonies, of dominating space travel and exploration.

Today, Spain remains a proud and relatively prosperous nation, but it has never again come close to the wealth and power it claimed for less than 400 years.

Whether America, if it continues to throw away its role in space, will fare as well – after just a little more than half that time – remains to be seen.