The recent downing of a U.S. Chinook helicopter in Afghanistan, presumably by al-Qaida or Taliban forces, killed 16 Americans and refocused public attention on the situation there.

Afghanistan was America's first post-9/11 war. It commanded full public support. Sharp, decisive U.S. military action there against al-Qaida and its Afghan Taliban hosts was entirely appropriate and, regardless of the sneering comments of President Bush's political counselor Karl Rove, a vigorous campaign against al-Qaida and the Taliban would have been carried out by a President Gore, as well as it was by President Bush.

The problem is that the job in Afghanistan was not completed. Instead, as is made clear by information such as the British "Downing Street" memo, the attention of the Bush administration had turned as early as the summer of 2002 to preparations for war against Iraq, for whatever reason.

Al-Qaida and the Taliban had in theory been driven out and some American resources continued to be devoted to the problems of Afghanistan, but as time went by it increasingly became apparent that as much remained to be done as had been achieved. Hamid Karzai, elected president in a reasonable facsimile of participatory elections, is perhaps the best thing that has happened to Afghanistan, and to America in Afghanistan. At the same time, his very credibility and decency will make it hard for the United States to walk away from him when that becomes necessary.

Loose ends include the fact that the mandate and authority of the Karzai government extend scarcely beyond Kabul, the capital. There have been many international pledges of aid to Afghanistan and some important basic reconstruction, but donors have not fulfilled their pledges, and development has been difficult to achieve in the face of ongoing security problems and classic Afghan corruption.

Of course, neither Osama bin Laden nor Taliban leader Mullah Omar has ever been caught, in spite of 3¹/₂ years of strenuous efforts involving U.S., Afghan and Pakistani forces.

Now the trouble seems to be getting worse. The Taliban seem to be coming back and, with them probably al-Qaida. U.S. forces appear to be particularly targeted. U.S. deaths in Afghanistan so far this year number 38, a rate 46 percent higher than last year's.

It may be too late now. The Iraq war did start before the Afghanistan campaign was completed and it continues to have first claim to U.S. forces and financial resources. It wouldn't be too late to shift U.S. resources from Iraq to Afghanistan to complete the job there. But that would require the Bush administration to, in effect, admit it was wrong in starting the Iraq war before finishing Afghanistan.

It is hard to imagine the Bush administration doing that. So what that means is that America is probably condemned to watch Afghanistan slide further into the kind of disarray that terrorists love, while Mr. Karzai and the democratic process associated with him becomes increasingly at risk. In the meantime, U.S. casualties will continue to go up.