It is an embarrassing thing if true, I think that's obvious.

"I didn't care about X until it came under attack" is not considered a damaging admission in most political discussions I've seen. While the usual meaning of that declaration is that the person has merely rallied around his political tribe's position, the person involved doesn't characterize it that way. What he knows is he didn't have a strong opinion, and now he does, and he assumes that he has good reason for it. He'll acknowledge that it's new while resenting any implication that the new opinion is irrationally-acquired. If you try to break down the why, he might notice that he's being irrational, but then you can flip a coin as to whether he'll be embarrassed and update rationally or be embarrassed and double-down.

I think it was an accident.

The blowout was an accident, yes. Things like people calling for a moratorium on drilling afterward were not, they were, in political parlance, "attacks". People of the tribe that pre-accident included drilling-is-bad among their beliefs used the accident as ammunition to attack their enemies, and people of the enemy tribe, many of whom had not actually thought about drilling in the Gulf before, rallied to defend when bombarded.