New Delhi, June 4 -- I don't care about the mid-terms," US President Donald Trump said last week. Conventional wisdom says he must. But maybe we should take him at his word. The president has, again and again, created unnecessary headwinds for Republicans.

Take his endorsement in the Texas Senate primary of scandal-ridden Ken Paxton over incumbent John Cornyn. In polls, Paxton had consistently trailed Democratic front-runner James Talarico relative to Cornyn. Now, Paxton's win is giving Democrats the best shot they have had in decades to flip a Senate seat in the nation's most populous red state.

Also, by waiting until the last minute to endorse Paxton, Trump ensured the Republican Party bled cash for months.

Zoom out, and the presiden...