FAIRFAX, Va. – Republican Mitt Romney accused President Barack Obama on Thursday of “failing American workers” by ignoring Chinese trade violations, and seized on new Federal Reserve attempts to boost the economy as proof the administration’s policies are not working.

Obama campaigned as commander in chief after the violent deaths of four U.S. officials at a diplomatic post in Libya. “No act of terror will go unpunished ... no act of violence shakes the resolve of the United States of America,” he said.

The president spoke in Colorado and Romney in Virginia with less than eight weeks remaining in a close campaign for the White House in tough economic times. The two states are among a handful likely to settle the race, and most polls rate Obama a shaky favorite.