The good news with respect to the unnecessary, now more than 7-year-old war in Iraq is that U.S. troop withdrawal is proceeding on schedule.

The current level stands at 85,000, down from a high of 155,000. The short-term goal is 50,000 by Aug. 31. The longer-term goal, set by an agreement between the occupation government of Iraq and the United States, is that all U.S. troops will be out of Iraq by the end of next year. The 50,000 remaining after Aug. 31 are not to be involved in security in Iraqi cities and are to make their primary activity the training of Iraqi security forces.

The remaining hurdles that the United States must cross to respect that timetable are partly in place because of the nature of Iraq and partly due to American elements that have an interest in keeping U.S. forces there for their own personal advantage. The degree to which one part of the equation is affected by the other is hard to ascertain, but the relationship is clearly there.

The essential problem is the ethnic and religious composition of the country. It is roughly 60 percent Shia Muslim, 20 percent Sunni Muslim and 20 percent Kurd. All of its leaders since independence in 1932 have wrestled with the problems these divisions present. This "nature of Iraq" part of its problems are most clearly illustrated at the moment by the current wrangle over establishing a post-election government.

The country held reasonably free and fair elections March 7. A different party, headed by a former prime minister, defeated the party of current Prime Minister Nouri al-Maliki. The result of this outcome, the overall confused party political situation in Iraq, and the total lack of a democratic tradition there -- in spite of the Bush administration's proclaimed hopes that a "liberated" Iraq could serve as a beacon of democracy in the Middle East -- is that nearly five months after the elections there is still no government in place.

Vice President Joe Biden traveled there earlier this month to admonish the Iraqis to get moving on that problem. The Iraqis ignored the advice and kept wrangling. There is some thought that the current crop of Iraqi politicians in place want to keep American forces in a perhaps realistic assessment that after they leave there will be a night of the long knives against politicians who collaborated with the American occupying forces.

The second group that has a vested interest in keeping U.S. forces in place in Iraq are the Americans who continue to profit from various construction and investment projects -- some paid for by the U.S. government -- that the presence of American troops makes possible.

Nothing that is foreseen in Iraq should interfere with the withdrawal schedule, with its milestones of Aug. 31 this year and Dec. 31, 2011. America is going home at the time of its choice for its own good reasons.

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