This column by ACRU Senior Legal Analyst Ken Klukowski was published June 21, 2011 on The Washington Examiner website.

President Obama’s war in Libya is now illegal, if it was ever legal. So House Speaker John Boehner can try to enforce the Constitution’s War Powers Clause, instead of the unconstitutional War Powers Act.

Sunday, June 19, marked 90 days since Obama began U.S. involvement in the conflict, thus reaching the deadline of the War Powers Act. Under that statute, the president must withdraw all military forces after 90 days if Congress doesn’t pass a resolution approving continued involvement in the war.

This statute–also called the War Powers Resolution–was enacted in 1973 when Congress overrode President Richard Nixon’s veto. It was intended as a check on every president’s powers.

The current situation is particularly interesting with the revelation that the two top lawyers who advise the president on war powers–the head of the Justice Department Office of Legal Counsel and the Defense Department’s general counsel–both advised Obama that his Libyan actions are “hostilities” subject to the War Powers Act. Attorney General Eric Holder agreed.

So the president took the extraordinarily-rare measure of seeking lawyers who would tell him differently. He found them in State Department Legal Adviser Harold Koh and White House Counsel Robert Bauer–both ultraliberal. (Koh would also like to be the first Asian-American on the Supreme Court.)

If Iran dropped bombs on Washington but said they weren’t “hostilities,” we’d still annihilate Tehran. And if Yemen furnished fuel and munitions, we wouldn’t like them very much, either.

The Libyan War is illegal, but not because it now violates the War Powers Act. Every president since Nixon has argued this statute as unconstitutional, including the only modern constitutional conservative president, Ronald Reagan.

They’re right; parts of the War Powers Act are unconstitutional. But so is Obama’s Libyan War.

As part of its separation of powers, the Constitution is full of clauses that are in tension. One is that only Congress can declare war, while the president is commander-in-chief of the military.

The president has inherent power as commander-in-chief for which he doesn’t need Congress. At minimum, he can act defensively to repel attacks on American soil, prevent imminent attacks, and protect American citizens abroad.

There are gray areas beyond those specifics. The president can probably use the military to fulfill defense treaty obligations and launch proportional reprisals against assailants.

But the line must be drawn somewhere, because the War Powers Clause provides that only Congress can declare war. The Constitution does not permit any president to decide unilaterally to overthrow foreign governments, redraw the world’s map, and put the national survival of the United States in jeopardy by committing us to a potential fight to the death with another sovereign nation.

Only Congress can make that decision, authorizing the president to use our military to wage war. Once authorized, only the president can actually order the military to attack. This is a two-step safeguard; both steps must be met before America goes to war.

Obama admits no Americans were endangered, nor our national security imperiled. Wherever you draw the line on presidential power, projecting military might onto foreign soil without provocation crosses that line. U.N. resolutions cannot substitute for Congress’ authorization.

This is not taking a stand on whether we should be at war in Libya. It might be good policy; it might be bad policy. The point is that it is Congress’ decision to make, not the president’s.

The recent lawsuit by 10 congressmen against the president will rightly be dismissed for lack of standing. Legal precedent makes clear that individual members cannot sue on behalf of the entire Congress.

But Boehner can now seek a full House resolution authorizing a lawsuit on behalf of the House, seeking court enforcement of the War Powers Clause. Individual members cannot sue, but a majority can.

It’s possible that a court would declare this unauthorized war unconstitutional, yet decline to order Obama regarding specific military decisions. But such a declaration would be immensely useful, tilting the political equation toward Congress’ position.

Bills defunding a war can be vetoed. After impeachment, removal from office requires two-thirds in the Senate. The courts should hold the Constitution does not require such extreme measures to curtail Obama’s unilateral war.

Congress should take him to court.