On Thursday, President Trump announced that National Security Adviser H.R. McMaster would be stepping down in April and that John Bolton, an extreme hawk and former ambassador to the UN, would replace him.

Liberals and Democrats do not like Bolton, and for rather obvious reasons. Among other things, he has advocated for preventive war with Iran and North Korea, championed — and still defends — the disastrous war in Iraq, wrote the foreword to a book by Robert Spencer and Pamela Geller, two prominent counter-jihadists, and has generally become the most hardline defender of military force on the American right.

But how is Bolton viewed in conservative circles? Is he aligned with mainstream Republicans, or is he too extreme?

I reached out to Tom Nichols, a professor of national security studies at Harvard and the Naval War College and the author of The Death of Expertise: The Campaign Against Established Knowledge and Why it Matters, to find out.

Nichols is a conservative who previously advised Republican Sen. John Heinz (who died in 1991) on defense and security affairs. I wanted to know what he thought of Bolton, and if he’s as worried as people on the left are.

A lightly edited transcript of our conversation follows.

Sean Illing

What was your initial reaction to Bolton’s appointment?

Tom Nichols

I don’t think anyone can be surprised. This is one of the few moves that Trump has been telegraphing for months. I’ve been dreading it, but I figured it was going to happen sooner or later, and not because of who Bolton is or what he believes but because he’s on television a lot, and the president appears to watch a lot of television.

To be clear, what Bolton believes and what the president ran on are diametrically opposed. So it’s not like Trump has found his soulmate in Bolton. At some point, you run out of options and serious people willing to take the job, so, naturally, Trump turns to someone on TV.

Sean Illing

It may strike some readers as odd to hear that Trump’s campaign vision and Bolton’s worldview are diametrically opposed.

Tom Nichols

Bolton’s philosophy is to extinguish all threats to the US by extending military force at will. Trump ran on “America First” and called the Iraq War stupid, whereas Bolton continues to defend the Iraq War and believes that we should stomp out danger wherever we think it will appear. So you’re either an isolationist guy, or you’re an elephant roaming the field stomping on every mouse that scares you, and Bolton is the latter.

My biggest fear in the early days of the Trump administration was, ‘What would happen if all these people were competent?’

Sean Illing

The word neocon is being tossed about a lot, but Bolton isn’t really a neocon because he doesn’t seem to care about promoting democracy abroad; he just wants to use American power to advance American interests, including waging preventative wars.

Tom Nichols

You’ve got it exactly right: Neocons are about using American force not just for interests, but to establish certain values and changes around the world.

I don’t think Bolton is a neocon because he doesn’t seem to care about democracy promotion; he’s an advocate of preventive war, which means acting way in advance to stomp out a perceived threat — that’s significantly different than preemptive war, which is about neutralizing an imminent threat.

Bolton’s approach to war is preventive, and I think it’s extremely dangerous.

Sean Illing

How is Bolton viewed in conservative foreign policy circles?

Tom Nichols

The hard right doesn’t like him because he’s not really an isolationist. The Bush-era people thought highly enough of him to make him UN ambassador, but nothing else. He’s developed this reputation as a master in-fighter, someone who can navigate the bureaucracy. But for a master in-fighter, he sure has been kept out of power for the last 20 years.

As far as I can tell, his reputation is that he’s a brilliant guy, but very strange in his views and more extreme than most conservatives. His threshold for going to war is much, much lower than most people on the right.

Sean Illing

The national security adviser’s job is to ensure that the president hears the views of the entire national security establishment, in order to help him or her make the best decision. An ideologue like Bolton seems like the worst person to have in that role, mostly because he’s likely to filter out facts and views that don’t align with his worldview.

Tom Nichols

In fairness, the NSA is almost always someone with an agenda. We’ve had very few truly honest brokers in this position, in part because the job is so loosely defined. Basically, the NSA position is whatever the president wants it to be. But if part of the job is to be the gatekeeper among all the competing institutional interests around the president, then Bolton is a terrible choice.

Sean Illing

Does Bolton’s appointment make war with North Korea or Iran more likely?

Tom Nichols

I think he’ll want to go to war, but I’m not convinced that he’ll succeed. Washington’s a big place with a pretty strong bureaucracy, and there’s an entire defense department that Bolton won’t control. Also, the Trump White House is chaotic. My biggest fear in the early days of the Trump administration was, “What would happen if all these people were competent? What happens if Michael Flynn and Steve Bannon turn out to be smart and effective?”

But they were all swallowed by the chaos of the administration, and got very little done. So I’m not convinced that Bolton is going to magically bring all this coherence to the West Wing. What he will be able to do is snuff out a lot of dissenting voices because of his proximity to the president, and that is certainly a concern.

Sean Illing

I guess the major worry is that nearly all of the so-called “adults in the room” have been purged. Defense Secretary James Mattis is the only man left standing at this point. That might increase Bolton’s influence.

Tom Nichols

Yes, that worries me. But I think a lot depends on who would replace Mattis in the event that he leaves. Historically, when there’s a clash between the defense secretary and the NSA, the defense secretary wins. The NSA is not in anyone’s chain of command, so he can’t start a war or order a strike. He’s merely an adviser to the president, and so his influence is constrained at an institutional level.

So people don’t need to panic right now. There might come a time when we should panic over what Bolton is telling the president, but I think it’s too early for that now. Concerned? Yes. Panicked? No.

Let’s wait and see if Bolton is actually able to accomplish anything.

[Author’s note: Nichols is speaking here in a personal capacity, and not as a representative of the US government or the Naval War College.]