A U.S. Senate committee, on a bipartisan vote, has approved President Barack Obama’s use of military force in Libya. It is expected the full Senate will follow suit.

Things are different among members of the House of Representatives, where some Democrats as well as Republicans worry about the cost in money — and the potential cost in lives — of U.S. intervention in Libya.

It is true, as Obama has pointed out, that no American lives have been lost in Libya and that there is no plan to send ground troops there.

Still, House members’ concern is understandable — for one reason often expressed regarding U.S. military ventures in the past: What is the “exit plan?”

Thus far, other than insisting Libyan dictator Moammar Gadhafi must step down, U.S. leaders have said nothing about how and when U.S. involvement would end. But when the war began, U.S. and other NATO officials predicted confidently Gadhafi would be gone quickly. That was three months ago.

What happens if the war drags on? How much longer are Americans willing to support intervention? Congress should insist on an exit plan.

— The Journal, Martinsburg, W.Va., July 1