The Left is mad at Robert Francis O’Rourke. After failing upward in his unsuccessful attempt to unseat Texas Sen. Ted Cruz, the gawky former congressman with a made-up nickname took his massive name ID, golden-boy status, and closet’s worth of sweaty blue button-ups and jumped face-first into the 2020 Democratic presidential primary. It took all of two seconds for “Beto” to wear out his welcome, going from the Next Big Thing to Another Privileged White Guy faster than an intoxicated O’Rourke could run away from a car he’d just wrecked. But rather than fade into also-ran obscurity, or return to Texas to run against Republican Sen. John Cornyn, O’Rourke has chosen to spend the few remaining weeks of his floundering presidential campaign saying what he really thinks out loud. The Left has now decided it's time for the onetime progressive darling to pipe down — or, better yet, get lost before the next primary debate in November. This is not because they disagree with him, necessarily, although some do, but because like bread before supper, too much honesty in a primary can spoil voters’ appetite in the general. At the Democratic primary debate in Houston on Sept. 12, O’Rourke proudly declared himself a gun-grabber. Asked by moderator David Muir whether critics were right that his plan involved gun “confiscation,” O’Rourke responded, “Hell yes, we’re going to take your AR-15, your AK-47.” To loud applause, he...