President Barack Obama recently signaled that in 2012 he intends to govern without Congress. His constitutionally questionable, so-called "recess" appointments during a time when the Senate was not in recess represents the latest in an effort by Obama to seize control in Washington, an effort that began with the appointment of numerous unaccountable federal czars at the beginning of his term.

It wasn't long ago that people on the left decried President George W. Bush for the notion of the "unitary executive," but even Bush refused to force a constitutional crisis by making "non-recess" appointments when Democrats pioneered keeping the Senate in session to block his appointments of conservatives. Once again, however, when it comes to  Obama’s expansion of executive branch power, the left falls into predictable, lock-step silence.

Michigan voters, where I’m running for the U.S. Senate, have started asking me. "What will this president do next to challenge our long-established Constitution?"

Examine the record of the president's hypocrisy and subtle attacks on the Constitution, and some clear indications emerge.

During the campaign, then-candidate Obama proclaimed that as a professor who taught constitutional law, Bush's use of signing statements was clearly unconstitutional. Now Obama has used signing statements 20 times, most recently on the National Defense Authorization Act.

In much the same way that the administration used its own reasoning to determine whether the Senate was in session, by using signing statements, the president has declared that his administration will interpret bills as it sees fit, not as Congress approved them. So much for the Constitution's separation of powers. The question has to be asked: If Obama saw it as unconstitutional under Bush, how does he justify its constitutionality now that he is president? Of course the answer is he cannot.

We all learned in grade school that the president's signature is required to sign a bill into law, but in 2011, Obama broke the precedent of the president signing all bills into law. Whether you agree with the Patriot Act or not, the final step for extending the law was a signature of the president by auto-pen.

Never before has a president delegated the authority to sign a bill to someone else, but this president has delegated signing authority to a machine.

The recent "recess" appointments are perhaps the most egregious of the president's actions, and in the context of the "governing without Congress," we should all be concerned about what he may do next. One area of particular concern that comes to mind is the terrorist detention facility at Guantanamo Bay, Cuba.

Though Obama has reversed course and adopted — and in some cases added — to counterterrorism authorities claimed by Bush, he still steadfastly refuses to back down on his promise to bring terrorists from "Gitmo," as it is called, to American soil.

The president has already set the stage for governing without Congress to force the Gitmo issue. In his signing statement to the defense bill, he objected to the bill's provisions about detainees, among others.

The president promised to close Gitmo, he has challenged Congress's ability to limit his authority in this area, and he has signaled with his non-recess appointments that he is looking for fights with an unpopular Congress. All the pieces are in place.

From my vantage point as a candidate and as a board member of LIGNET.com, a Washington, D.C.-based intelligence analysis and forecasting service, I believe that the American people must be vigilant.

Not only is closing Gitmo bad policy, the constitutional implications if the president should move to do so along with pushing the limits of his power to appoint could have broad, unintended consequences.

Just because you agree or disagree with the president's policy, does not mean that circumventing our constitutional process should ever be acceptable. The responsible course is for all on the left and right to oppose the president's attempted power grab, and to demand he use his powers clearly enumerated in the Constitution to achieve his policy goals while respecting the separate and enumerated powers of the Congress. To do otherwise is to risk awakening one day to a president you disagree with claiming broad powers to force policies just because he said so.

So much for the Constitution.

Peter Hoekstra represented Michigan's 2nd Congressional District from 1993 until 2010. He is running for the U.S. Senate.