WASHINGTON, Dec. 14, 2004 — There appears to be an almost endless supply of fighters willing to die for their cause in Iraq. Suicide bombers have routinely struck U.N. buildings, hotels, and checkpoints since the end of major combat in the country. The weapon of choice is usually an explosive-packed automobile, but explosive vests have been used as well. U.S. intelligence officials say the majority of the bombers are not foreign fighters, as many believe. "The big myth is that there's an endless supply of suicide bombers, that the foreign fighters are everywhere. That's the story everybody wants to hear,...