The cry on Broadway used to be that the Brits were not only coming but conquering; now, with the arrival in the West End of Margaret Edson’s Pulitzer winner Wit, Warren Leight’s Tony winner Side Man, Neil LaBute’s Bash, and a revival of David Mamet’s American Buffalo, the balance of trade appears to be shifting dramatically. Conventional wisdom – not to mention union vigilance – dictates that a successful New York-to-London transfer replace the original cast with recognizable British stars; in recent months, however, several American producers have thrown caution to the wind, sticking with often unknown Americans in what are, after all, American roles. Daryl Roth, a producer of Wit, remarks that while an actress such as, say, Maggie Smith “would make a splendid Professor Bearing,” the play has been “brilliantly served” by Kathleen Chalfant. “The rhythms of a play like Side Man are so uniquely American,” says Roy Gabay, one of that show’s producers. “Why wouldn’t you want to see Americans in it?” And so Side Man’s British production will star 90210 thespian Jason Priestley (pictured). How do the Brits feel about the invading Yanks? “It’s about time the Americans started coming through,” says Irish playwright Martin McDonagh (The Beauty Queen of Leenane). “Just as long as we keep the French out. That’s the main thing for me.”