Republicans do not publicly break with President Trump that often (see: the Ukraine allegations). So the nearly wholesale GOP rejection of Trump’s decision to pull troops out of Syria is worth further study. Top Senate Republicans, such as Senate Majority Leader Mitch McConnell (R-Ky.) and Senate Judiciary Chairman Lindsey O. Graham (R-S.C.), said they disagree.

Rep. Adam Kinzinger (R-Ill.) is another one of those critics. He serves on the House Committee on Foreign Affairs. On CNN’s “Cuomo Prime Time” on Monday night, Kinzinger offered a long explanation of why Republicans disagree with Trump that is worth examining. In essence, he thinks Trump is choosing his reelection over what’s right for the country. Let’s break down what he said.

Kinzinger: Well, first off, the president has to lead. That’s where a lot of times, when people look at public opinion polls, it’s America’s knee-jerk reaction to want to get out of any war, I understand that. Because they have to have leaders that explain why we’re doing it.

Kinzinger is indirectly accusing Trump of doing the politically expedient thing. Conflict is generally unpopular with the American public, and we’re nearing an election with ominous warning signs for Trump. In addition, Trump has made moves before to get out of Syria — in December, his defense secretary resigned over it. So what Trump is doing makes sense politically, Kinzinger is saying, but sometimes you have to prioritize foreign policy over politics, especially now that Trump has much more information at his disposal as commander in chief. He should at least try to leverage the power of the presidency to explain to Americans why he is not fulfilling a campaign promise to get out.

This echoes McConnell’s statement that Trump should “exercise American leadership.” Here is more from Kinzinger:

We’re actually generally a pretty peaceful country. So when the president says I’m getting out because of all these reasons, he talks about endless war, he talks about that kind of stuff. The reality is, is terrorism’s real. And the decision to end the war is not really ours to make when you have a whole group of folks that say, you know, look, we’re going to go and create a terrorist attack, whether it’s in Iraq or the United States. That’s not our choice. They haven’t changed their mind on it.

Kinzinger brings up two main points. Yes, the United States has been involved in conflicts in Iraq and Afghanistan for nearly two decades. But outside of that, America is not engaging in a ton of other conflicts. Syria is the exception.

His second point is Trump’s campaign promise was unrealistic when it comes to keeping Americans safe. You can’t be entirely at peace when terrorism is a threat, he is saying. In an interview with Fox News’s Martha MacCallum, also on Monday, Kinzinger said: “That’s not the choice that the United States determines, how long we’re going to fight terrorism. It’s a decision the terrorists make, because they determine if they’re going to kill innocent people.”

Here, Kinzinger is referring to the main reason the United States sent troops to Syria in the first place: to battle the Islamic State. The group has been dispersed but is not entirely vanquished, as Trump likes to say it is. Outside of a key border zone between Syria and Turkey, “the risk of an Islamic State comeback is most grave,” reports The Washington Post from Lebanon.

This echoes what Graham said on Twitter, as well.

Kinzinger: And so, yes, it may have been a campaign promise, but when you become president, I think it has to be more than a campaign promise. And secondarily, too, what we’re talking about is the exact kind of fight that those that we’re against, for instance, the Iraq war and everything else we’re talking about. You know, a small group of American soldiers that can empower local indigenous forces to fight that fight. That’s exactly what our troops are doing there. And now to say this is an endless war, I have to vehemently disagree.

Another fear among those who oppose the Syrian pullout is that the United States will be putting Syrian Kurds, an ethic minority who helped U.S. troops battle the Islamic State, at risk to players in the region like Turkey. That will destabilize the region in a way that benefits the Islamic State. These all play off each other.

To make his point, Kinzinger draws a comparison between a destabilized Syria and a destabilized Iraq and the subsequent eight-year Iraq War. Trump’s not in an endless war, he argues. But by leaving a smaller conflict, he risks creating an endless war, Kinzinger warns.

The key line is this: “When you become president, I think it has to be more than a campaign promise.” That brings us around to Kinzinger’s first point, that he thinks Trump is putting political expediency over choosing a more difficult route. The logical conclusion to what he’s saying is some Republicans, like Kinzinger, believe Trump, three years in, does not get what it means to be president or how to do it.