when do wars become unpopular?

It took a dozen years, but a plurality of Americans now view the Afghanistan war as a mistake, according to a new Gallup Poll. The accompanying news release also includes the tipping points for other major wars, showing a much shorter span of support.

Public opinion soured on the Iraq war after only 15 months. In Korea, views changed after only 6 months, when the war also changed with large scale Chinese intervention discredited General MacArthur's promise of an early victory. In the case of Vietnam, the tipping point was October 1967, just three years after the Gulf of Tonkin incident and Congress' authorization of force and a little over two years after the first major U.S. troop escalation.

The obvious lesson is that Americans like short, successful wars and grow weary of long, unresolved conflicts. Impatience isn't necessarily a virtue, but it is a fact of political life.