It would require a torpedo to the bow from the Mueller report or some other enormous scandal and a significant ideological betrayal on something extremely important, like a Supreme Court nominee. The first might be possible, although not likely, and the chances of the second seem remote.

It’s going to take something more than tariffs on steel, lack of interest in tackling entitlements and constant talk of an impending infrastructure proposal to detach him from the Republican rank and file.

The promoters of a Trump primary challenge still haven’t come to grips with how intertwined Trump’s fate is with the party’s.If Trump becomes vulnerable to a primary challenge, it’s a sign that something very bad has happened that won’t be contained to him. Say it’s proof of a criminal conspiracy with the Russians. Is the rest of the Republican Party that has defended Trump so vociferously during the Mueller probe going to emerge from that unscathed? Say it’s a sudden economic downturn. What’s the case that such an event wouldn’t tank the GOP generally?