Leaders of the U.S. intelligence community said the government shutdown creates opportunities for U.S. enemies and is compromising American national security.

The comments at a Senate hearing — by Director of National Intelligence James Clapper and National Security Agency Director Gen. Keith Alexander — injected a potent new argument into the shutdown debate, which both parties seized on.

Lawmakers passed a bill, signed by President Barack Obama, to exempt the U.S. military from payless paydays as they stay on the job to defend the country.