Good lord. This is much nastier than the ballyhooed Tucker/Ralph Peters punch-up on Tuesday night. Before the clip’s halfway through they’re sneering at each other for holding sinecures. It’s one of the most bitter cable-news segments I’ve ever seen. Is there history between them that I don’t know about?

Credit Tucker for inviting on a vocal critic to continue the argument over interventionism. That was bold and shrewd, and the dispute marks a legit ideological flashpoint on the right. If Fox primetime’s options are between this and spinning Don Jr’s “I love it!” response to an invitation to collude with Russia on Hillary oppo, give me this. I think this fight’s more evenly matched than the Carlson/Peters bout was too. Boot lands a few solid shots that Peters never thought of, noting that Carlson himself was an Iraq War proponent himself in the early days and confronting him about what he thinks should happen with Syria. Tucker doesn’t answer that squarely but presumably his response would be some variation of “It’s none of our business.” Okay, but if Russia and Iran take active roles in shaping the future of the country, the new Syria and its long-term influence on the region may end up being our business. This is the eternal argument between interventionists and isolationists — not so much whether to intervene but how long to wait. Wait too long and you get 9/11 and a nuclear-armed North Korea. Refuse to wait and you’re managing 15 years of counterinsurgency in Iraq in the name of taking out a WMD program that didn’t really exist.

What I can’t understand about Tucker is why he continues to take such offense at Boot’s moral judgment. If you’re an isolationist, you can either embrace amorality (not immorality, per Carlson’s complaint) or try to turn the accusation around by arguing that interventionism and the destruction it brings inevitably is the less moral of the two options. Tucker instead spends most of his time grousing that it’s unfair to treat his check-the-box denunciations of Putin as perfunctory just because he thinks there might be some value to partnering with Russia in Syria. But then, when Boot accuses him of wanting to aid a country that’s engaged in war crimes, Carlson scoffs and callously says something like, “Every war involves war crimes.” (The audio’s not clear since the two spend most of their time talking over each other.) If your gut reaction to what Assad and Putin are doing in Syria is, essentially, “sh*t happens” then you can’t get too offended when people around you act judge-y. Either own the amorality — we should care only about American interests, however unfortunate the results in human terms — or make the case that U.S. intervention would have produced a less moral outcome in Syria than staying out did. “Sh*t happens” is bound to please no one.

Watch to the end or you’ll miss Boot calling him a Trump shill. Geez.