So much for the Great Right Hope in 2020. “I will not be a candidate,” former senator and now-CBS News contributor Jeff Flake announced to start his debut on CBS This Morning. Flake urged someone to run against Donald Trump in the Republican primaries, but in almost the same breath called it an impossibility:

JOHN DICKERSON: Before we start, I want to find out if you want anybody to call you “President.” Are you — have you thought about running in 2020? Are you going to run?

FLAKE: I’ve always said that I do hope that there is a Republican who challenges the president in the primary. I still hope that somebody does, but that somebody won’t be me. I will not be a candidate.

DICKERSON: Did you look into being a candidate to run against the president, and what did you learn from that investigation that somebody else who might run would have to consider?

FLAKE: I think anyone who’s in the Senate looks at that at some point.  But there really isn’t a path right now that I could see, certainly not unless you’re willing to be out there already, raising a lot of money, and basically living on the road right now. It’s a difficult path anyway. The RNC and the president’s campaign are now melded. They’re trying to do anything they can to squelch any opposition. I still hope that some — and some are still talking about it — do run. I think that’s healthy, and I’m not a fan of this president, but it won’t be me.

Flake’s point about senators and their ambitions are well taken in this cycle, when it appears that every other Senate Democrat will toss their hats into the primary. However, it also seems a bit curious. Flake’s trying to get others to enter into a primary challenge, but there’s almost no one in the GOP better positioned than Flake to do so. He wrote a book about his distaste for Donald Trump’s politics and tactics, and in doing so got the highest profile of Trump critics within the GOP. Why isn’t Flake still “talking about it,” when he did plenty of talking about opposing Trump over the last two years?

Who else does Flake foresee in the role he wants filled, especially given the very real obstacles Flake identifies? Only John Kasich might fit the bill, but so far he seems less than anxious to launch a primary campaign too. Trump critics have talked up Larry Hogan, but the Maryland governor hasn’t done much to raise his status as an in-party opponent of Trump, and he would likely be too moderate and his state too liberal to sustain a challenge anyway.

The lesson here seems to be that it’s easier to talk about a primary challenge than to do the hard work in putting one together. We can expect Flake to do a lot of talking about primary challenges in his new role as a CBS contributor. We can probably expect a lot more talk from a lot of other Trump opponents, too. Don’t expect to see much action, though, while talk remains a lot more lucrative and safe.

Update: Headline changed at noon ET, just to shake things up a bit. Original headline: “Flake: GOP needs to primary Trump — but it ain’t me, babe.”