ST. LOUIS – Two days ago, Senator Barack Obama said he had not been clear enough in explaining his Iraq policy. Today, there was a different rationale.

The confusion was not his fault, Mr. Obama said, but rather the media’s for seizing on three words he uttered in Fargo, N.D., when he suggested he would be open to “refine my policies” on Iraq.

“I was surprised by how finely calibrated every single word was measured,” he said, speaking to reporters as he flew here from Montana.

Mr. Obama touched off a stir on Thursday when he said he would consult American military commanders in Iraq before saying whether he would continue to pursue a proposed timetable of withdrawing combat troops within 16 months of taking office. A few hours later, he took the rare step of calling a second news conference to reiterate his commitment to end the war.