President Obama may not think he had to ask Congress before approving a military intervention in Libya. But now that it’s started, Congress should be asking some hard questions of him.

First among them are, what is the goal of this operation and how does it end? How far should we be willing to go to remove Moammar Gadhafi from office, and is any outcome short of his removal acceptable?

Additional Photos

In this March 19, 2011 photo provided by the U.S. Navy, Aviation Electrician's Mate 2nd Class Joseph Fremen, assigned to Helicopter Sea Combat Squadron 22, calibrates the forward looking infrared system of a Sea Hawk helicopter on the flight deck of amphibious assault ship USS Kearsarge in the Mediterranean Sea. After a barrage of attacks by sea-launched Tomahawk cruise missiles on Libya Saturday, an array of U.S. warplanes _ including several Air force B-2 stealth bombers _ followed in the pre-dawn hours Sunday with a coordinated assault using precision-guided bombs, according to a U.S. military official. amphibious assault ship USS Kearsarge (LHD 3) Libya Odyssey Dawn AP

We in Maine are represented by a bipartisan delegation in Washington, whose members have access to the administration in a wide range of ways. We would like to see them use their influence to help shape and clarify this latest American military mission in the Middle East.

Six months ago, Gadhafi’s brutal rule of Libya was not even on a top 10 list of America’s foreign policy challenges. Now, the fast-moving events of this “Arab Spring” have left the international community with the choice of either taking action or idly watching a dictator massacre his political opposition. And we would not be the only ones watching: Every other dictator and pro-democracy movement would also be paying close attention.

But no matter how hard people call for us to “do something,” we can’t do just anything. And clearly articulated goals are the key to developing a successful strategy. In his letter to Congress, Obama laid out more than one aim. He said the initial motive is humanitarian, with the goal of protecting Libyan opposition members from slaughter.

But he also stated a broader military goal, saying that if Gadhafi is unchecked, instability could spread throughout the region and could “ignite wider instability in the Middle East, with dangerous consequences to the national security interests of the United States.”

It would be best if the air power used by the United States and our allies provides enough cover for opposition forces to overthrow Gadhafi, but what if it isn’t? Is the next step arming and equipping the rebel forces, or sending American troops to topple Gadhafi?

Maine’s members of Congress are in a position to ask these questions. U.S. Rep. Chellie Pingree and Sen. Susan Collins serve on the Armed Services committees in the House and Senate. Sen. Olympia Snowe serves on the Senate Intelligence Committee and has been a sought-after vote from the administration on a variety of domestic issues. Rep. Mike Michaud also has shown a willingness to speak up when he disagrees with the president.

All four should press these questions before these unfocused goals give us an ambiguous result.