One party (in fact, essentially one wing of the Republican party), seeking the elimination or delay of Obamacare precipitated a government shutdown and threatened to force a default on U.S. debt. Period. There was no corresponding threat or demand on the Democratic or White House side; having gotten the Affordable Care Act into law three years ago, they are not in the situation of saying, “Pass Obamacare or we shut ‘er down.”
That looks right at first glance, but it doesn't entirely explain why we have a crisis. Poniewozik's account needs a slight correction. The decisive fact is that the House of Representatives precipitated a government shutdown. That body happens to be controlled by the Republican party, but how you approach the crisis depends, to some extent, on whether you perceive your antagonist as merely a party or a branch of the government. As has been stated repeatedly by partisans and nonpartisans alike, the House has the power of the purse and has used it in the past to force government shutdowns while negotiating with the Senate or the President. The Republican argument for the past two weeks has been that the President has an obligation to negotiate with the House of Representatives. The President's view, and that of most Democrats, is that he doesn't have to negotiate with the Republican party. From that perspective, which Poniewozik ignores, the White House and the Democrats have made a "corresponding threat or demand:" fund Obamacare or we shut 'er down -- or default. That doesn't put Democrats less in the right on the issue of Obamacare itself, practical issues notwithstanding, but it does help account for the crisis without heaping 100% of the blame on the Republicans or the House as a body.
Poniewozik probably anticipated this argument. Here's the next paragraph of his article:
That’s the situation. To accurately describe it, as news coverage should, is not to endorse an ideology. It’s not to say that Obamacare is good or bad. It’s not to say that Republicans do or don’t have good reasons to oppose it. It’s not to say that Democrats have or haven’t sought political benefit in the aftermath. But it correctly places the impetus where it belongs.