Former State Department official Marie Harf said it's unclear what message President Trump was trying to send with his warning to Iranian President Hassan Rouhani.

Following Rouhani's statement that hostile U.S. policies toward could lead to the “mother of all wars," Trump took to Twitter to address the Iranian leader.

In all caps, Trump told Rouhani to never threaten the U.S. again or face historic consequences.

"WE ARE NO LONGER A COUNTRY THAT WILL STAND FOR YOUR DEMENTED WORDS OF VIOLENCE & DEATH. BE CAUTIOUS!" Trump wrote.

"Or what? What's the president going to do?" Harf wondered on "America's Newsroom."


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She said it's easy to fire out a strongly-worded late night tweet, but that doesn't establish a policy or convey a clear message.

"He's going to attack Iran?" Harf said.

Bill Hemmer pushed back, asking if Trump should be "passive" toward Iran, as American leaders have for decades.

"You don't conduct foreign policy by tweet," Harf stated.

Republican strategist David Avella said Trump is making it clear to Iran that his administration is very different from his predecessor's and that he will take threats of "death to America" seriously.

"Let's hope these tough stances will get Iran thinking correctly that taking the U.S. on is a bad move," Avella said.

Harf pointed out that Trump also talked tough on North Korea, but Kim Jong Un's rogue regime has not taken any concrete steps toward denuclearization.

See more from the "America's Newsroom" panel above.


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