As I watched Taxi Driver for the first time in twenty-odd years, I was reminded of M. Night Shyamalan's Unbreakable.  Not because Unbreakable comes anywhere close to Taxi Driver in terms of cinematic merit, but because Taxi Driver seemed to be aiming at the same broad theme--a comic book-style hero in a gritty, adult world. Because, if anything, Travis Bickle seems to fit quite closely a real world Batman, enraged by the injustices of the world, unable to fit in, and ultimately taking the law into his own hands.  He has a raw honesty--in sizing up people, in not being offended by a porn movie--and an uncontrollable urge to act on a primal sense of right and wrong.