NEW YORK--Politics makes artists stupid. Take "My Name Is Rachel Corrie," the one-woman play cobbled together from the diaries, emails and miscellaneous scribblings of the 23-year-old left-wing activist who was run over by an Israeli Army bulldozer in 2003 while protesting the demolition of a Palestinian house in the Gaza Strip. Co-written and directed by Alan Rickman, one of England's best actors, "Rachel Corrie" just opened off-Broadway after a successful London run. It's an ill-crafted piece of goopy give-peace-a-chance agitprop--yet it's being performed to cheers and tears before admiring crowds of theater-savvy New Yorkers who, like Mr. Rickman himself, ought...