Donald Trump provided a few surprises last night, mainly in his more statesmanlike demeanor, but one answer in particular looked more like an abrupt about-face. Trump has positioned himself as less interventionist abroad, deriding George W. Bush for the war in Iraq in particular, and occasionally has suggested that we leave ISIS to the Arabs. Last night, however, Trump insisted that the US needs to put boots on the ground to crush ISIS, and not just a few special-operations boots either:

https://www.youtube.com/watch?v=PZTD-WEhJ9M

GOP frontrunner Donald Trump suggested at Thursday’s CNN Republican presidential debate in Miami that he would be willing to support a massive ground force to take on ISIS.

This is a shift for Trump, who has, as a presidential candidate, often portrayed himself as less hawkish than his Republican opponents.

Trump made the troop comment in response to a moderator’s question as to whether he would follow a military commander’s advice to increase the number of ground troops to fight the terrorist group.

“We really have no choice,” Trump said. “We have to knock out ISIS. We have to knock the hell out of them. We have to get rid of it and then we have to come back here and rebuild our country, which is falling apart.”

Radio host Hugh Hewitt pressed on specific numbers.

“I would listen to the generals,” Trump said, “but I would – I’m hearing numbers of 20 to 30,000. We have to knock them out fast.”

How much of a flip-flop is this? It’s hard to tell, because Trump has been hard to pin down on this point. Last May, he bragged to Greta van Susteren that he had a foolproof plan to defeat ISIS, but that he didn’t want to publicize it. “I don’t want the enemy to know what I’m doing,” he explained, “but there is a method of defeating them quickly and having total victory.” On the other hand, Trump railed against the Bushes for getting the US involved in a ground war in Iraq in 2003 just this past January, picking up on the false “Bush lied” meme that anti-war activists use to push isolationism. It certainly represents a tonal shift from Trump’s earlier embrace of war skeptics and rejection of traditional Republican interventionist policies.

If nothing else, this position of putting 20-30K boots on the ground shows some recognition of reality when it comes to defeating ISIS, although that’s hardly a secret plan. Defense and counterterrorism experts have discussed that figure for two years, and even some higher numbers than that. Even the White House acknowledges that such a force could succeed in dislodging ISIS from its current strongholds, but claims that it would make little overall difference and that it would encourage ISIS recruitment to have American boots on the ground. The only way to defeat ISIS is to surround it and take away its territory, and the only way to do that is to field an army sufficient to the mission. Whether those are American boots, or Saudi, or even Martian, that’s the only way to defeat an entrenched infantry and a quasi-state. Until someone does that, ISIS will continue to exist, metastasize, and threaten the rest of the world.