President Obama has announced that the United States will deploy an additional 30,000 troops to Afghanistan, mostly to the Pashtun provinces of Helmand and Kandahar in the south, where the Taliban are in control. Though it suggests a goal of helping the Afghan state weather a Western withdrawal beginning in July 2011, Obama's plan is likely to make the circumstances of the withdrawal more unpleasant.

In his long-awaited address, the president presented a series of objectives but no clear strategy. Although al-Qaeda hasn't returned to Afghanistan in great numbers, he conceded that it maintains "safe havens along the border." Yes, on the other side, in Pakistan. Later, he articulated a goal to "disrupt, dismantle and defeat al-Qaeda in Afghanistan and Pakistan."

Even as Obama spoke of focusing U.S. war efforts and preparing for withdrawal, he made it sound as though the United States should be fighting in two countries instead of one, aggregating distinct enemies together and fighting them all.

The signs were evident even in a Freudian slip in a Tuesday White House press briefing, when a senior administration official said, "our goal is to prevent the return of the Taliban -- I'm sorry, of al-Qaeda -- and to prevent the Taliban from overthrowing the Afghan government."

The new troops will not stay in southern Afghanistan long enough for the Afghan army to establish control there and build functioning government institutions. And, indeed, the presence of foreign troops fighting on behalf of a corrupt government in Kabul only makes that government more unpopular, which helps the Taliban grow more entrenched, even as they take losses.

Obama's speech was just a speech. His point about arming Afghan militias and building security from the ground up is where the country is actually headed. But as the Taliban continue to gain on Kabul from several directions -- including the north, where new troops would make more of a difference -- Obama's plan will make it harder for the government to survive and likely that the United States will leave Afghanistan looking worse than it does now.