“I always worry about the debt ceiling,” Ms. Yellen told The New York Times in an interview on her flight from New Delhi to Bali, Indonesia, in which she urged Democrats to use their remaining time in control of Washington to lift the debt limit beyond the 2024 elections. “Any way that Congress can find to get it done, I’m all for.”

Democrats did not heed Ms. Yellen’s advice. Instead, the United States has spent most of this year inching toward the brink of default as Republicans refused to raise or suspend the nation’s $31.4 trillion borrowing limit without capping spending and rolling back parts of President Biden’s agenda.

The real story is that the Senate was split 50-50 and Democrats were missing a vote even for reconciliation. I'm sure you can guess whose vote it was:

The administration has determined that if it were to go the reconciliation route on the debt limit, it would face likely opposition from Sen. Joe Manchin (D-W.Va.).

....Already, Manchin has expressed reluctance to act on the debt limit with only Democratic votes, though he’s declined to rule it out completely. “I don’t think it should go to reconciliation,” he said Tuesday. “My goodness, it’s something we’ve always worked together on.”

According to Politico at the time, "That’s left White House officials to all but abandon efforts for a lame-duck move they once hoped might head off a potentially disastrous showdown with the House GOP majority next year."

In short, we are now facing a debt ceiling crisis thanks to Joe Manchin. That's it.

pdq wrote:
The whole point of Manchin is to divide Democrats, for his personal West-Virginia benefit.