Editor's note: John Avlon is a CNN contributor and senior political columnist for The Daily Beast. He is the author of "Wingnuts: How the Lunatic Fringe Is Hijacking America."
New York (CNN) -- It's déjà vu all over again.
Congressman Dennis Kucinich is talking impeachment. Ralph Nader is grumbling that the president of the United States is a "war criminal." Michael Moore is venting his spleen on the subject of U.S. hypocrisy.
What's different is that the president provoking the professional protest crowd this time is a Democrat.
For all the overheated anger at President Obama from the far right, where people have called him a socialist and worse, the fact is that Obama isn't considered a ideological soul mate by the far left. Far from it.
One of the reasons: Libya is just the latest example of Obama embracing national security executive powers that have prompted some liberals to claim that he is leading George W. Bush's third term.
First, there was the decision to increase the number of troops in Afghanistan. Then came the realization that closing Guantanamo was easier said than done. There is the administration's use of wiretaps and escalation of predator drone strikes. And now the airstrikes in Libya, engaged without extensively consulting Congress.
An objective assessment of the Obama record on foreign policy shows that he has not been the soft liberal ideologue that conservatives want to run against. An excellent book by my Daily Beast colleague Stephen Carter, "The Violence of Peace," analyzes Obama's War Doctrine at length from a legal, but readable, perspective. Carter writes, "On matters of national security, at least, the Oval Office evidently changes the outlook of its occupant far more than the occupant changes the outlook of the Oval Office."
While Obama has changed the unilateral style of the Bush administration, he's kept much of the substance. He has drawn down troops in Iraq, as promised. But on many other fronts, he has found that campaign rhetoric often does not square with the responsibilities of governing.
Because many on the left define themselves in opposition to authority, they are historically quick to turn on presidents of their own party for being insufficiently liberal -- whether it is Truman's and Kennedy's Cold Warrior enthusiasm, LBJ's escalation of the Vietnam War, Jimmy Carter's budget cuts or Bill Clinton's welfare reform.
Kucinich has been joined by a small chorus of voices from the left in Congress in condemning the president. These include: Barbara Lee (who was the lone vote against the Afghanistan invasion after 9/11); Michael Capuano (last seen telling a union rally "you need to get out on the streets and get a little bloody"); Maxine Waters (who repeatedly pulled a proto-Joe Wilson by calling President Bush a "liar") and Sheila Jackson Lee (a House Foreign Affairs committee member who last year said "Today we have two Vietnams, side by side, North and South").
This cast of characters is a fair representation of the far left in the minds of the right. And yet they are now among Obama's fiercest critics. That should be a reality check that resonates with centrist and independent voters.
But you've got to give Obama's critics on the left points for ideological consistency. They are apparently not swayed by simple partisanship. Some of their newfound allies on the right, however, will have a harder time making that case.
For example, former House Speaker Newt Gingrich, a potential Republican presidential candidate, took aim at the Libya intervention, calling it "opportunistic amateurism without planning or professionalism." A few days earlier, as Alana Goodman pointed out in Commentary, he had been criticizing Obama's inaction, saying, "This is a moment to get rid of [Gadhafi]. Do it. Get it over with."
Libertarian, and longtime critic of the neo-cons, Ron Paul can at least claim consistency in his circulation of a congressional resolution "expressing the sense of Congress that the President is required to obtain in advance specific statutory authorization for the use of United States Armed Forces in response to civil unrest in Libya." Among its supporters to date is Detroit Democrat John Conyers -- Ron Paul's philosophic opposite on almost everything. The Beltway buzz was that committed partisans finally found something upon which they could agree.
Obama can be criticized for delay in his decision to impose a no-fly zone. He can be criticized for communicating more with allies in advance of multilateral action than with members of Congress. He can be criticized for lack of military experience before entering office and insufficiently clear directives after.
But the secret hiding in plain sight is that Barack Obama was never the simple "anti-war candidate" his leftist supporters hoped or his conservative opponents feared. While he opposed Iraq from the beginning, he supported escalation in Afghanistan, even proposing drone strikes into Pakistan during the campaign.
The criticism of the professional left and the professional right is likely to heat up if the conflict drags on. Michael Moore's tweeted sarcasm will set the tone for other liberal Obama critics on the netroots: "We've had a "no-fly zone" over Afghanistan for over 9 years. How's that going? #WINNING!"
But Moore's suggestion that Obama return his 2009 Nobel Peace Prize ignores the substance of what the president said in his acceptance speech: "I believe that force can be justified on humanitarian grounds, as it was in the Balkans, or in other places that have been scarred by war. Inaction tears at our conscience and can lead to more costly intervention later. That is why all responsible nations must embrace the role that militaries with a clear mandate can play to keep the peace."
The opinions expressed in this commentary are solely those of John P. Avlon.