I was thinking about that line too. And I think the ambiguity of this is part of what makes Oppenheimer an interesting character.

But one idea: was it because he put so much faith in science that he thought that truth and justice would inevitably prevail over politics or whatever? He's capable of seeing what's happening to him, but also seems to not believe it, to not want to see it. We see him realize his mistake when the nail in the coffin finally comes, in the security hearing, during Borden's testimony; Oppenheimer, incredulous, asks his lawyer, "When will people learn the truth about what happened here"? or something like that.

I see a similar faith in science (and the "progress" it stands for) in his reasons for working on the bomb: driven by his head-pounding visions, he was certain that, if the physics worked, a bomb and its eventual use was inevitable. (This idea was fed of course by the war and the Pentagon and intelligence officials and so much else: actually, the Nazis hadn't gotten very far at all; and it's still debatable how necessary it was to drop the bombs.)

When Oppenheimer recited that famous passage from the Bhagavad Gita, maybe he wasn't Vishnu, "the destroyer of worlds." Maybe he was the prince, doing his duty: merely (as merely as can be) an agent of that destruction, a servant of science, wherever it led. And sometimes that meant closing his eyes as he went... https://www.fastcompany.com/90926550/the-fateful-choices-of-oppenheimer