When George W. Bush was asked earlier this year whether all American troops would someday come home from Iraq, he called it an "objective" and said it would be "decided by future presidents and future governments of Iraq."

He wasn't kidding.

Gen. George Casey, the top U.S. commander in Iraq, said over the weekend: "I think as long as the Iraqi security forces continue to progress and as long as this national unity government continues to operate that way and move the country forward, I think we're going to be able to see continued gradual reductions of coalition forces over the coming months and into next year."

If that sounds hedged and heavily qualified, that's because it is. And if it sounds like something you've heard before, well, that's because it's that, too.

In March 2005, when there were about 138,000 U.S. troops in Iraq, Casey said: " By this time next year -- you know, you base all of your planning on assumptions. Assuming that the political process continues to go positively, and the Sunni are included in the political process, and the Iraqi army continues to progress and develop as we think it will, we should be able to take some fairly substantial reductions in the size of our forces."

In July 2005, when there were about 135,000 U.S. troops in Iraq, Casey said: "I do believe that if the political process continues to go positively and if the development of the security forces continues to go as it is going, I do believe we'll still be able to take some very substantial reductions after these elections in the spring and summer of next year."

Number of U.S. troops in Iraq today: 133,000.

Now, to be fair, the first day of summer is still a week away. And Casey has usually been careful not to attach specific numbers to his predictions about troop withdrawals. But we'd submit that a drop from 138,000 to 133,000 troops over 15 months is something less than a "substantial reduction" in most Americans' eyes; if the "reductions" continue at this pace, the last U.S. soldier will come home from Iraq in the fall of 2039.

Maybe we're being too gloomy in the wake of the death of Abu Musab al-Zarqawi. But maybe not. As officials tell the New York Times, the Bush administration "has begun to look at the costs of maintaining a force of roughly 50,000 troops [in Iraq] for years to come, roughly the size of the American presence maintained in the Philippines and Korea for decades after those conflicts."