attack that crippled iran s centrifuges? one author says stuxnet was different. this was traditional national security taking down inline with your city council sanctions some of the worst regimes on the planet trying to develop some of the world s worst weapons. reporter: but the sands and sony hacks, experts say, could embolden those regimes to take it one dangerous step further. other sectors such as our finance and banking and power plays and the like that provide life and safety functions for our economy and for our country could be the potential next target. reporter: but one expert says what may keep iran, north korea, or another u.s. enemy from hacking america s power grid or other infrastructure is the knowledge that if americans start getting hurt or killed by those attacks, the retribution will be severe. brian todd, cnn, washington. well, the man accused of bombing the boston marathon finish line was in court thursday for the first time in