Micah Zenko follows up on his argument from last week that the administration has set an unrealistic goal in saying that it will “destroy” ISIS:

Yet, while mitigation and containment will drive the U.S. counterterrorism strategy regarding ISIS as a reality, the Obama administration (and Congress and the media) will pretend that the strategic end state is to defeat and destroy them. So when you hear the White House promise to destroy ISIS, don’t believe them, but consider why it is politically mandatory that they make such an outrageous and impossible claim.

There are several reasons why presidents feel compelled to declare their intention to “destroy” an enemy group or state. Because foreign threats are constantly being blown out of proportion, and because the rhetoric used to whip up public and Congressional support for military action usually requires describing each new enemy in the worst, most terrifying terms, it becomes very difficult to “settle” for a goal of partial victory or containment. If you accept that an enemy poses a dire and supposedly “unprecedented” threat to the country, it seems impossible to manage such a threat, and so it seems necessary to pursue a goal of destroying that enemy that isn’t going to be achieved because anything less seems “weak.” By pretending that the threat is “imminent” when it clearly isn’t, and by pretending that the U.S. faces a direct threat when there is no evidence that it does, administration officials and many people in the media stoke the public’s fear and anxiety to such a degree that it then becomes politically untenable to say that U.S. policy is to seek anything less than the complete elimination of the threat.

Even when the president acknowledges that there is no evidence of a direct threat to the U.S., as Obama has done in this case, he can still appeal to the slippery logic of preventive war that insists that there might one day be some direct threat. That frees him from the burden of having to show that the group in question has the ability to threaten the U.S., and allows him to claim an absurdly vague definition of “defending” Americans from a group that was previously not targeting them. There have always been hard-liners in U.S. foreign policy debate that have derided the idea of managing or containing a threat, but in the last fifteen years with the normalization of preventive warfare this has become a mainstream and almost consensus view. Even though “preventive” war often increases the number of threats to the U.S. and sometimes creates threats where none had existed, it has gained wide acceptance among elected members of both parties. It is the more activist and aggressive approach, and that seems to offer policymakers and the public reassurance that a threat is being “handled” despite the fact that this approach is almost certainly not diminishing the threat and may be exacerbating it.

Another reason that American politicians don’t like to be seen as “settling” for something less than “destroying” the enemy is the influence of the memory of WWII. That has taught generations of our politicians that the only truly desirable victory is a total one involving the destruction or unconditional surrender of the enemy. Containment worked well enough in the Cold War, but when faced with much weaker adversaries it no longer seems necessary to tolerate the existence of groups and governments that could eventually pose some threat to America. At the same time, the danger from these much weaker adversaries is inflated beyond all recognition so that the public is misled into believing that the danger must be eliminated with urgent military action, and it is simply taken for granted that whatever “must” be done is also possible for the U.S. to do at an acceptable cost. The trouble is that the goal is most likely unachievable, and pursuing that goal is all but guaranteed to cost the U.S. far more than anyone was ever willing to lose when the campaign began.