Senator and presidential candidate Ted Cruz (R-Tex.) speaks at the Georgia Republican Party’s state convention on May 15, 2015, in Athens, Ga. (David Goldman/AP)

As he prepared for his presidential run over the last year or so, a hawkish Sen. Ted Cruz has said U.S. policy in the Middle East and elsewhere is a mess because of President Obama’s weakness — particularly his failure to enforce his own “red line” after the Syrian regime used chemical weapons.

“A critical reason for [Vladimir] Putin’s aggression has been President Obama’s weakness,” the Texas Republican said in a typical appearance, on ABC News last year. “You’d better believe that Putin sees that in Syria,” he added. “Obama draws a red line and ignores the red line.”

This takes quite a lot of chutzpah, even by Cruz standards. It’s true that Obama didn’t enforce his red line in Syria — in large part because Cruz rallied opposition to bombing Syria.

I was reminded of Cruz’s hypocrisy this week by Rep. Adam Kinzinger, an Illinois Republican who served three tours in Iraq and two in Afghanistan as an Air Force pilot. Kinzinger, who favors a muscular foreign policy, was one of a small group of House Republicans leading the effort to give Obama authority to bomb Syria in 2013 — but they were undone when Cruz began declaring that bombing the Syrian regime would make the United States “al-Qaeda’s air force.”

“I think Ted Cruz bears some responsibility for not enforcing the red line,” Kinzinger told me. “The Republican support began crumbling the more Cruz spoke. His words implied that anyone who voted for strikes would be acting as an agent of al-Qaeda.”

Condemning Obama for failing to enforce the Syrian red line after blocking him from enforcing the very same red line? This is vintage Cruz, who I’ve long suspected to be a charlatan.

As I’ve written before, I first encountered him when he was an ambitious staffer on George W. Bush’s presidential campaign 15 years ago, and he positioned himself as a young striver, not a hard-edged ideologue.

But when the tea party rose, Cruz opportunistically aligned himself with those views.

Now, isolationism is fading within the conservative movement, and Cruz is opportunistically becoming more of an interventionist.

Even Sen. Rand Paul (R-Ky.), the leading voice of isolationism in the GOP presidential field, disavows the label and has gone from saying there is not “clear-cut American interest” in fighting the Islamic State to saying he would vote to do so “in a heartbeat.”

As Politico’s Michael Crowley observed this week, Sen. Marco Rubio (R-Fla.), now trying to establish himself as the leading hawk among the presidential contenders, was also opposed to bombing Syria after Obama left the question to Congress in 2013. But he wasn’t as instrumental as Cruz in denying Obama congressional support.

Back in 2013, when Obama was seeking congressional approval for Syria airstrikes, Cruz said his constituents were telling him not to “put us in the middle of a sectarian civil war, particularly when doing so would help al-Qaeda terrorists.” He belittled the significance of the chemical-weapons red line, saying, “It appears what the president is pressing for is essentially protecting his public relations.”

Sen. Ted Cruz has declared his candidacy for president. The Texas Republican is known for his fiery oratorial style. Here's his take on immigration, Obamacare and, well, green eggs and ham. (Gillian Brockell/The Washington Post)

Previously, Cruz had spoken out on the Senate floor against Obama’s plans to arm the Syrian rebels, saying, “It seems we are backing into an intractable crisis where there are no good actors but plenty of bad outcomes for America.”

But last year, Cruz became bellicose. “What we ought to have is a directed, concerted, overwhelming campaign to take them out,” Cruz said of the Islamic State in another ABC interview. In an interview on Fox News, he accused Obama of operating a “photo-op” foreign policy and of being “unserious” in handling the Islamic State. At another point, he said the United States should “bomb them back to the Stone Age.”

In a December 2014 speech, Cruz shamelessly declared, “President Obama announced his now infamous red line in Syria and then did nothing.” That “gave the green light to aggressive or oppressive regimes across the globe that America is not to be feared.”

This is exactly what Kinzinger argued — back in 2013, when Cruz was arguing the other side. Kinzinger agreed with Obama’s red line on chemical weapons, and he thought Obama should have struck the Syrian regime without congressional approval.

But once Obama dropped the issue on Congress, Kinzinger said, support for military action collapsed because of “people like Ted Cruz out there campaigning against this thing.”

And now Kinzinger is campaigning against the opportunistic Cruz; he backs Jeb Bush for president.

“If you’re somebody who is going to say you stand on principle,” the congressman said, “you can’t have foreign policy views that shift in the wind.”

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