Next year, with Trump in the White House and the GOP in control of Congress, Obama’s moral clarity and rousing defense of progressive values will be more vital than ever. By going silent, while Republicans try to dismantle his signature achievements, Obama would deprive the Democrats of their most powerful voice at a time when the opposition party needs it most.

In a podcast interview posted Monday with his longtime political adviser David Axelrod, Obama made clear he doesn’t want to lead the resistance to the new president. He allowed that he might take on Trump “a year from now or a year and a half from now or two years from now”—if “foundational issues about our democracy” are at risk—but Obama has other post-presidency priorities: vacationing with his wife, drafting his next book, developing new Democratic talent, and, before any of that, getting some serious shut-eye.

No one begrudges Obama some R&R after eight taxing years. But the memoir can wait. And while he should absolutely promote the next generation of Democrats—and work on redistricting with Eric Holder, as he’s also planning to do—those projects will take many years. The left has more immediate, pressing political concerns. Until the opposition finds a new, dynamic leader, it should be able to count on the great one it’s already got.

This doesn’t mean Obama should be tweeting back at Trump. Obama told Axelrod he shouldn’t be part of the “day-to-day scrum,” and he’s right. But the president is uniquely positioned to be an outspoken ex-president, and their are a host of reasons he should be emboldened to do so. Maybe it’s with more thinly veiled statements like Tuesday’s. Maybe it’s with explicit criticism doled out discerningly. But he’d be making a mistake not to step up when his party needs him—especially, though not exclusively, when his own legacy is at stake.