“Nothing will be gained by spending our time and energy laying blame for the past.” So declared President Obama, after his commendable decision to release the legal memos that his predecessor used to justify torture. Some people in the political and media establishments have echoed his position. We need to look forward, not backward, they say. No prosecutions, please; no investigations; we’re just too busy.

And there are indeed immense challenges out there: an economic crisis, a health care crisis, an environmental crisis. Isn’t revisiting the abuses of the last eight years, no matter how bad they were, a luxury we can’t afford?

No, it isn’t, because America is more than a collection of policies. We are, or at least we used to be, a nation of moral ideals. In the past, our government has sometimes done an imperfect job of upholding those ideals. But never before have our leaders so utterly betrayed everything our nation stands for. “This government does not torture people,” declared former President Bush, but it did, and all the world knows it.

And the only way we can regain our moral compass, not just for the sake of our position in the world, but for the sake of our own national conscience, is to investigate how that happened, and, if necessary, to prosecute those responsible.