“THE SIMPLE TRUTH,” said Senator John McCain at the Council on Foreign Relations in Washington, D.C., on Wednesday, “is that we do not have sufficient forces in Iraq to meet our objectives.” President Bush disagrees. His administration has given frequent assurances that there is no need for additional U.S. troops in Iraq. But Senator McCain, who visited Iraq in August, before the recent spike in attacks on U.S. forces, thinks that administration policy doesn’t address the realities on the ground. “It’s a mystery to me why [more troops] aren’t forthcoming,” he said.