Peter Beinart is on the right track here , but his recollection of the last twenty years is a little off:
When the Cold War ended, however, the idea of a foreign power dominating Western Europe or East Asia, or creating a beachhead in the Western Hemisphere, suddenly seemed fanciful. As a result, the language of national interest largely disappeared [bold mine-DL]. It has been replaced by a discussion of foreign “threats” and American “values.” But without a definition of interests, it’s impossible to define what constitutes a threat. And without a definition of interests, supporting American “values” is a limitless pursuit. Americans will never reach a consensus on where exactly our interests lie, but just reintroducing the concept suggests an overdue recognition that because America’s power is finite, its interests must be too.
Beinart is right that post-Cold War politicians and policymakers began to refer to a much more expansive and virtually limitless set of U.S. “interests and values,” but his description omits a few important things. The trouble here wasn’t that American politicians and officials stopped referring to the national interest, but that the meaning of the phrase became so amorphous and was so frequently conflated with vague “values” talk that it could be invoked to justify almost anything just about anywhere in the world. If no clear U.S. interests have been implicated in a foreign conflict or political dispute, invoking a defense of “values” has been the default way to lure Americans into supporting different kinds of interference in other countries that they might otherwise reject. Meanwhile, if there is even the slightest U.S. interest in a particular country, its importance is grossly exaggerated to get the U.S. more deeply involved in whatever events happen to be taking place. The distinction between vital and peripheral interests to which Sen. Paul referred , never upheld very clearly during the Cold War, began to be ignored on a regular basis during the ’90s, and this has only become worse over the last decade.
The distinction between interests and values has also been ignored more and more often in recent decades. While they are certainly not alone in doing this, neoconservatives are the most frequent offenders when it comes to blurring or erasing the lines between interests and values. As recently as last year, John McCain wrote , “our interests are our values, and our values are our interests.” Leave aside for the moment that this sounds more like the mantra of a cult member than a serious statement about U.S. foreign policy. It is a common refrain that we hear all the time, and it is almost always used to agitate for U.S. involvement in conflicts where America has little or nothing at stake. McCain happened to be writing about Syria in that case, but he could just as easily have been referring to Libya or Ukraine or virtually anywhere else.
Linking and eventually identifying “interests and values” reached its apogee during the Bush years. Indeed, Bush’s Second Inaugural included  the deluded (or dishonest) proclamation that “America’s vital interests and our deepest beliefs are now one.” Likewise, the problem of the last twenty years isn’t that American politicians and policymakers have ceased referring to national interest, but that many of them tend to treat even relatively minor foreign disputes and conflicts as things that threaten “our vital interests” and some go beyond that to pretend that “our vital interests” are at stake wherever our “values” are coming under attack. It isn’t enough to “reintroduce” the phrase national interest to the debate. It is essential that it be defined in a much less expansive, bloated way than it has been for the last twenty years, or else it will continue to be used to justify endless meddling all around the world.