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John Kerry's nine reasons for action in Syria

Secretary of State John Kerry condemns Syria for mass killing. NBC's Andrea Mitchell reports.

U.S. Secretary of State John Kerry made the case on Friday for why the U. S. should punish Syrian President Bashar al-Assad for a "brutal and flagrant" chemical weapons attack that it says killed more than 1,400 people in Damascus last week.

In a bold, passionate speech delivered from the Treaty Room at the State Department, Kerry laid out a raft of evidence he said showed Assad's forces were behind the attack, and the U.S. government released an unclassified intelligence report at the same time including many of the details.

Here are the highlights from Kerry's memorable delivery.

On chemical weapons

The secretary of state, explaining what "we really know that we can talk about," went into detail on the Assad regime's chemical weapons program and how it planned for last week's attack, according to intelligence reports.

On social media

Kerry addressed the power of the Internet in showing the world the effects of the chemical attack. "Just 90 minutes later all hell broke loose in the social media," he said.

On the horror of the attack

Doctors saw "not a scratch, not a shrapnel wound, not a cut, not a gunshot wound. We saw rows of dead lined up in burial shrouds," Kerry said.

John Kerry says, The USĀ  government now knows that "at least 1,429 Syrians were killed."

On the victims

The secretary of state made a point of noting the precise number of victims the United States government has identified: 1,429 Syrians, including at least 426 children. "Even the first responders — the doctors, nurses and medics who tried to save them — they became victims themselves. We saw them gasping for air, terrified that their own lives were in danger," he said.

On Assad's cruelty

"This is the indiscriminate, inconceivable horror of chemical weapons," Kerry said, following his description of the attack. "This is what Assad did to his own people."

John Kerry says, "The question is what are we - we collectively - what are we in the world going to do about it."

On history

Kerry spoke about the peril of inaction in Syria. "The primary question is really no longer, what do we know. The question is what are we — we collectively — what are we in the world going to do about it."

On the need to punish the Syrian president

 Kerry, in a line repeated often Friday on Twitter, called Assad "a thug and a murderer" and addressed the consequences of not acting against him.

On U.S. responsibility

In an elegant phrase, Kerry made his case for U.S. involvement succinctly: "My friends, it matters here if nothing is done."

On war fatigue

The secretary of state also acknowledged that the American public, exhausted by wars in Iraq and Afghanistan, might be wary of another engagement. "Believe me, I am, too," Kerry said. "But fatigue does not absolve us of our responsibility."

More on Syria from NBC News: