Gen. Jack Keane (Ret.) joined Sean Hannity tonight to react to the U.S. launching airstrikes in Syria in response to a chemical weapons attack that killed dozens of civilians.

He said this is a "major setback" for Russia and Iran, close allies of the regime of Syrian President Bashar-al Assad.

Keane said that U.S. officials blame the Assad government for the chemical attack, and these airstrikes are a sign that the U.S. is open to taking a more active and aggressive role in the Syrian civil war.

"This is an incredible message," Keane said. "It should have been sent many years ago by the Obama administration."

He added that this also shows China that Trump will use the military option if he has to.

Now, he said, China might be more receptive to cooperating with the U.S. to deal with North Korea's burgeoning nuclear program.

Keane said that after eight years of passivity under President Obama, we now have a man of action as commander-in-chief.

"He's taken a very limited action, but it sends an incredibly strong message to our adversaries in the world, who are paying attention, believe me," Keane said. "We have a decisive president who is going to act on behalf of U.S. national interests and the interests of our allies."

"That is an unequivocally, loud, clear message."

Watch more above, and stay with Fox News Channel for all the latest on the Syria airstrikes.

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