More than a few conservatives and libertarians are very uncomfortable with America taking an active role in political and military situations around the world. Jerry Pournelle has written many articles lamenting the change from Republic to Empire, and he is far from the only one. I'm not that happy about it myself, but see it as a necessary evil. On the other hand, the foundation of almost every rotten empire in history usually involved the concept of "necessary evil." Yech.

The libertarian ideal would have America be neutral, like Switzerland, and deal only with direct threats to the United States. In the 1700s, this could work. In the 20th century, it isn't so clear any more.

Suppose we had chosen to sit out WWII, while successfully defending our own waters and borders. A successful missile defense system. What would the world be like now? What if Japan had been smart enough not wake the sleeping giant and attack Pearl Harbor, but just busied itself devouring Asia? What if Hitler had decided not to declare war on us, and the rest of the allies were unable to talk us into joining them?

Where would South Korea be now? Taiwan? Eastern Europe? Heck, WESTERN Europe? Can anyone think of a plausible scenario where America is isolationist through the twentieth century, that would not have resulted in most of the rest of the planet conquered by collectivist monsters, warring with each other, using the technology that extends their reach far beyond what tyrants of the past would have accomplished? What would our economy be like isolated from the planet? Could we ignore it all, hoping the width of the oceans and our defense barriers stifled the radiation and the stench of billions of corpses?

I've got no easy answers. Neither does Pournelle, or anyone else who has dealt seriously with this problem.

Oh, there's speculation...

In the science fiction book "Probability Broach" by libertarian L. Neil Smith*, North America is a loose (VERY loose) confederation of libertarian/anarchists, with an almost non-existent central government. In the alternate universe where this takes place, an invasion of Europe by a tyranny is met by official neutrality on the part of the North American Confederation, while thousands of heavily armed private citizens (they're ALWAYS heavily armed) streams over to Europe to repel the invasion on their own. Think Abraham Lincoln Brigade by an order of magnitude.

The alternate reality timeline at the end of the book is priceless, and I may reproduce it in another post some time.

*Here's his opinion on the Iraq war.