Daniel W. Drezner is a professor of international politics at the Fletcher School of Law and Diplomacy at Tufts University and a regular contributor to PostEverything.
President Trump unveiled a new strategy for the U.S. war in Afghanistan on Aug. 21. (Victoria Walker/The Washington Post)

In his televised speech last night, the president flip-flopped his position on the war in Afghanistan. We know this because, to his credit, Trump explicitly copped to it:

My original instinct was to pull out, and historically I like following my instincts. But all my life, I have heard that decisions are much different when you sit behind the desk in the Oval Office. In other words, when you are president of the United States. So I studied Afghanistan in great detail and from every conceivable angle. After many meetings over many months, we held our final meeting last Friday at Camp David with my Cabinet and generals to complete our strategy.

There’s a lot to unpack in that paragraph. Watching it live, when he said “I studied Afghanistan in great detail and from every conceivable angle,” I literally laughed out loud. Let’s be blunt: The only printed material that Trump has studied in great detail from every conceivable angle are periodicals that contain glossy centerfolds.

That said, I do believe Trump’s claim that he preferred to pull out and subsequently changed his mind. The question is why. For all the myriad ways the president tried to claim that his strategy of “principled realism” was different from President Barack Obama’s Afghanistan strategy, it’s pretty much the same. The Trump administration cares a little less about democracy promotion and a lot less about civilian casualties than the Obama administration. The president suggested that India could play a stabilizing role, which is true only in the sense that such a move would guarantee that Pakistan would play an even more destabilizing role.

As my colleagues Thomas Gibbons-Neff and Anne Gearan write:

By tweaking a course set by President Barack Obama, Trump suggests that he, like Obama and President George W. Bush before him, is facing the bleak reality of Afghanistan: There is no fast or politically palatable way to win, but losing quickly isn’t an acceptable option, either.

“I think mush is what we have, and unfortunately I fear it’s where we’re headed,” said Vikram Singh, a former senior adviser on South Asia at the Pentagon and the State Department who is now a vice president at the liberal Center for American Progress.

Given that this goes against Trump’s instincts, why the shift? Two big factors pushed him in the same direction. The first, obvious one is path dependence: Given the situation today, there is no magic formula to change things for the better with dramatic action. As Trump himself said, “No one denies that we have inherited a challenging and troubling situation in Afghanistan and South Asia, but we do not have the luxury of going back in time and making different or better decisions.” Just as a retrenchment-minded Obama confronted the reality of U.S. forces being in Iraq and Afghanistan, so does a retrenchment-minded Trump. Sometimes foreign policy is all about coping with no-win scenarios that you inherited from previous policymakers.

The second factor is one that I have been hammering again and again, but it bears repeating: Trump is an exceptionally weak commander in chief. He lacks the gravitas and expertise to countermand his military advisers, even when his instincts push him in that direction. Trump also lacks any civilian staffers with the knowledge and wherewithal to put an unconventional solution onto the table. Steve Bannon apparently backed a hare-brained scheme to outsource the war to Erik Prince’s military contractors, but with Bannon’s departure even that idea was scotched.

What was unusual about this decision is that when faced with a choice between an unappetizing status quo and a future of even worse alternatives, Trump chose the status quo. He does not normally do this — except when it comes to decisions involving the military. That is consistent with what he did in Syria in the spring.

Trump’s weakness as commander in chief has the paradoxical effect of expanding America’s military footprint in the world:

The U.S. military is not really all that hawkish, but the armed forces do tend to prefer more firepower to less in those conflicts where they already have a footprint. So while the military might not advocate for any new conflicts, they have and will advocate for more resources to prosecute the conflicts they are enmeshed in.

Which means that, contrary to some who believed that Trump was the less hawkish candidate in 2016, Trump will repeatedly defer to the military in his grand strategy. No matter what he claims, he has no better ideas.

This means longer and bloodier wars.