Nobody — remember this — neither Hitler, nor Lenin, nor any despot you could name, ever came forward with a proposal that read, ‘Now, let’s create a really oppressive and evil society.’ Hitler said, ‘Let’s take the means necessary to restore our national pride and civic order.’ And Lenin said, ‘Let’s take the means necessary to assure a fair distribution of the goods of the world.’
In short, it is your responsibility....not just to be zealous in the pursuit of your ideals, but to be sure that your ideals are the right ones. That is perhaps the hardest part of being a good human being: Good intentions are not enough. Being a good person begins with being a wise person.
--Antonin Scalia, at a commencement speech in 2010