When I posted these clips to Twitter, a reader replied that of course Rubio is a Reagan disciple. He supports amnesty, doesn’t he? Zing.

Fairly or not, a dynamic has developed within the grassroots right online that you can’t be pro-Trump and pro-Rubio. You can be pro-Trump and pro-Cruz because you think America needs a populist, because Washington is so sleazy that it needs to be cleansed with fire. You can be pro-Cruz and pro-Rubio because you think America needs a conservative, because Washington has moved so far left that only a hard push to the right can restore the country’s equilibrium. But you can’t be pro-Trump and pro-Rubio. They’re matter and anti-matter. Trump will deport the illegals, or so he says. Rubio would legalize many. Trump says what he thinks, no matter who he offends. Rubio is scripted and soft-spoken, and styles himself as a uniter. Trump wants to make nice with Putin and disdains nation-building. Rubio loathes Putin and favors aggressive interventionism. Trump represents “white identity politics.” Rubio represents diversifying the party. Up and down the line, substantively and stylistically, you find contrasts. Trump wants to make America great again; Rubio can’t tell you fast enough that he thinks America is the greatest country ever.

What makes these two Rush clips striking is that, for most of the past eight months, to the consternation of many anti-Trump listeners, he’s had nothing but warm words for Trump. Occasionally he’ll scold him for using McConnell-esque lines of attack on Cruz, like calling Cruz a maniac for clashing with other Senate Republicans, but much of the past year has been an exercise in mainstreaming Trump as a legitimate vessel of populist conservative anger despite his many, many prior heresies against conservatism. For most other grassroots righties, if you feel that way about Trump, chances are high that you also think Rubio’s an establishment RINO, an avatar of “business as usual” Republicanism whose Gang of Eight stain can never be scrubbed clean. Not Rush. On the contrary, listen below and you’ll find him blowing up that argument, which is at the absolute core of Trump’s and Cruz’s case against Rubio. Rush, almost singularly, is pro-Trump and pro-Rubio. Huh.

Notably, he was a little less pro-Trump than usual today:

And Donald Trump — I don’t know if you’ve forgotten — one thing that I remember is that he went out and again tried to criticize Cruz. Cruz here is the front-runner. Cruz is not the enemy. Hillary Clinton is the enemy. Ted Cruz is not “a nasty guy.” Ted Cruz is not a Canadian. Ted Cruz is none of that. He’s not mean-spirited. Ted Cruz doesn’t want anybody to die in the streets. Nobody’s gonna believe that, especially when you offer that criticism sounding as though it could come from Bernie Sanders.

In a Republican primary, you do not win if you’re going to sound like a liberal Democrat criticizing Ted Cruz. And it wasn’t just health care. How many of you remember (I pointed this out when it happened) Mr. Trump pointing out that you can’t do anything if you can’t make deals, can’t cooperate? Part of his criticism of Ted Cruz is he’s hated; nobody likes him. Trump said, “I can do deals with Harry Reid and Pelosi. I know these people. I like these people. Schumer? I can do deals.” No, no, no, no! We don’t want to do any more deals with these people. We want to beat those people. There are many things that harm Mr. Trump, but not showing up at the debate is not one of them.

As nasty as the Trump/Cruz war in Iowa was this month, both between the candidates themselves and among their supporters online, a Trump/Rubio war would be 10 times as bad precisely because of the stark choice they present. Cruz can be viewed (although he doesn’t have to be) as a compromise between the two — plenty conservative enough for Rubio fans, if not nearly as likable, and populist enough for Trump fans, especially as a contrast to Rubio. A Trump/Rubio race would end up as a proxy war between two radically different visions of the party. Rush would naturally caution listeners from reading too much into any soundbite, especially ones as short as these, but it’s hard not to come away from this thinking that if forced to choose between those two visions, despite his admiration for Trump in various ways, he’s with Rubio. Luckily, thanks to Cruz’s win last night, the odds of any voters having to face that binary choice — at least anytime soon — are slim.