From Pat Buchanan's American Conservative, a good article discussing the outlines of the debate within the foreign policy establishment at the end of the Cold War.  Obviously, for the author (and the American Conservative in general), it is the intervionism of the 90s and the unwillingness to scale back our military and other geopolitical committments that has led us inexorably to "empire." 

It is interesting to consider that the US used the 1990s as what I almost look to as a "vacation from history."  No major opponents like Nazis, Imperial Japanese, or Communist Soviets (or other sympathizers) were facing us.  The threat of thermonuclear annhilation was gone (or so it has been perceived) and all things domestic (and local) could be focused on.  Any of those foreign "interventions" that we did engage in were really more like social work because we felt bad when the Serbs killed Bosnians (though not bad enough when the Hutus were killing the Tutsis).  I think the debate discussed here is good and useful (Ron Paul taps this vein very strongly in his surprisingly effective insurgent campaign).  That said, I always ask this question, "If Not Us, Who?"  Power hates a vacuum, someone will fill it, period.  We were in a position to say that the nation to fill it would be the US.  While that has lead to some uenviable situations and, yes, maybe has even led to some backlash, does anyone imagine that any other nation would have done better? 

With power comes responsibility, we had (and have) great power and, consequently, we must exercise our responsibility.  "Empire" is is phrase misused to describe what we have established post World War II.  In no way do we exercise dominion as did the Romans or the British (or other European colonial powers of their day).  We have acted when necessary for the most part (if, perhaps, rashly at times).  The economic system most closely related to us has helped lift millions out of poverty in other parts of the world as nations like India and China have "plugged" in to the international architecture we largely erected.  That is not an outcome to be morose about.  Yes, we sometimes have gone overboard and done what was not completely necessary as well as made costly mistakes, but again "If Not Us, Who?"