In an official statement, President Trump described the recent chemical attack in Syria as "reprehensible" and went on to argue the "heinous actions by the Bashar al-Assad regime are a consequence of the past administration's weakness and irresolution." In other words, he blamed former President Barack Obama.

Returning to a common theme of his campaign, Trump's statement concluded, "President Obama said in 2012 that he would establish a 'red line' against the use of chemical weapons and then did nothing. The United States stands with our allies across the globe to condemn this intolerable attack."

Trump's criticism of Obama's policy on Syria goes back to 2013. A private citizen at that time, he argued that the U.S. should not get involved in the conflict.

On Tuesday, Trump's statement did not include what — if anything — his administration would do about the recent attack or what his posture will be toward Assad in light of it. Press secretary Sean Spicer said that the president's statement "speaks for itself." He said Trump is meeting with his national security team, is "alarmed" at what is happening and that there will be further discussions with allies about the appropriate action. He added, "I think, at this point, as things develop, I'm not ready to talk about our next step, but we'll get there soon."

Spicer also referenced Obama's red line comment, in which the then-president said, "A red line for us is we start seeing a whole bunch of chemical weapons moving around or being utilized. That would change my calculus. That would change my equation."

At the time, Trump didn't say anything about it on Twitter. It wasn't until Syria started dominating the headlines in the summer of 2013 that Trump began weighing in. Two days after the U.S. concluded the Assad regime had used chemical weapons, Trump tweeted that the U.S. "should stay the hell out of Syria."

His message: Stay out; Syria is not America's problem. And Trump was relatively consistent on that as the conflict in Syria intensified and the Obama administration contemplated an expanded U.S. role.

In late August 2013, the U.S. and international community concluded that the Syrian government had again used chemical weapons. The Obama administration was reportedly considering a military strike against Syria to send a message, and private citizen Trump questioned whether it was worth it.

And long before he was a candidate, Trump was critical of politicians — including Obama — for telegraphing their military strategy.

On Aug. 30, 2013, a U.S. intelligence assessment found more than 1,400 Syrians were killed in the chemical weapons attack. Trump's tweets focused on how that made the U.S. look.

The next day, Aug. 31, Obama announced he would seek congressional approval to carry out strikes in Syria. This was widely seen as a way to back away from the red line he had drawn, putting the responsibility for a decision to escalate involvement in Syria on the shoulders of Congress.

It rapidly became clear that Congress wasn't going to be able to agree on authorizing force — and that Congress really didn't want the responsibility.

On Sept. 5, 2013, Trump's concern was that Obama had set the red line in the first place.

A day later, seemingly joking, Trump offered his own solution: Use Obamacare in Syria so "they would self-destruct."

Secretary of State John Kerry ultimately worked out a multinational agreement, including Russia, in which Assad would agree to give up his chemical weapons. Trump's assessment was not positive.

In the end, he concluded the way Obama had handled Syria made America look weak.

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