Good read, and a good argument:
I think he’s right: Obamacare was passed by two means, really (maybe more, but at least these two):
Raw arithmetic of a Democratic majority, Democratic Senate, and Democratic President.
Consensus that you can - or at least ambivalence to the idea that you can - pass expansive entitlements without paying for them with current money.
As for (1), the Iraq War certainly had a great deal to do with ushering in the raw math needed to pass something like Obamacare, as the author explains (I think, rightly). Democrats knew it, and seized on it (and it almost still didn’t pass), but
As for (2), the GOP deserves lots of blame for that as well. Under any form of reasonable fiscal sanity, there is no way the nation could afford Obamacare, even if everyone thought it was a fantastic idea and there were enough votes in support of the “idea” of it. But because Republicans were hard-charging, “deficits don’t matter” for years (decades, really), their own ideas and policies (see Medicare Part D) paved the way for Obamacare being passed when it should have been met with a “yeah, right” even amongst those who had some support for it.