KABUL, AFGHANISTAN—As late as the third call to prayer Wednesday afternoon, Afghan warlord Najibullah Muhibi had still not determined which side—Taliban insurgents or U.S. Army—he would provide with useful intelligence that day. "Boy oh boy, I tell you, both allegiances just seem so tempting today!" Muhibi said through an interpreter contracted by the State Department. "I suppose I should just pick whichever one strikes my fancy. Either way, I make a lot of money, no? What a glorious day to be alive!" After much thought, Muhibi resolved to share with the Americans the location of a Taliban weapons cache, the directions to which involved driving directly past a concealed roadside bomb.