Democrats famously have a tendency to regard themselves as a party in disarray and are uniquely prone to letting down their activist base by underachievement. But the truth is that narrow congressional majorities often produce devastating legislative setbacks. Ask the Republicans who watched their own domestic policy Great White Whale, a repeal of Obamacare, go down the tubes in the wee hours of July 28, 2017. The coup de grâce was administered by the late John McCain, whose famous “thumbs-down” gesture signaling his decisive vote against the last-gasp “skinny repeal” bill became the symbol of Republican frustration (much like Manchin’s pronouncements against this or that Democratic priority today) in the 115th Congress…

So what’s the lesson for Democrats? The trouble they’ve had isn’t simply about their alleged disunity, or the president’s alleged lack of leadership, or even about the pernicious use of leverage by Manchin or others to throw sand into the legislative machinery. It all comes back to the shakiness of small congressional majorities, and the power of the Senate filibuster, and the creaky imperfections of the budget process as the only way around the filibuster in important respects. Institutional reforms are ultimately the only solution — and yes, Manchin is a huge obstacle to those as well — rather than some surgery on the soul of the Democratic donkey and its various limbs and organs.