Recent caches of Iranian made explosives that have given the militants a greater punch against U.S. forces' armor has shed a stark light on their involvement. It's gotten people's attention better than the intelligence stories that have been cropping up since before the U.S. invasion.
While the administration continues to readjust its rationale for war and recast current progress in the most favorable light, the political and military calculus involved in any effort to leave a stable Iraq behind becomes increasingly complex.
There is seemingly little the U.S. could do to restrict Iranian influence in Iraq. Perhaps that has contributed to new talk of pressuring Iran over their nuclear program, especially the use of the phrase, "military option as a last resort." Certainly enough evidence has come to light that the Iraq invasion was not a use of force as a last resort, but a preordained certainty.