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Story highlights

Susan Rice implicitly criticized the President's frequent use of Twitter

Rice was national security adviser under former President Barack Obama

(CNN) —  

The United States could “squander our greatness” by failing to put country over party, former national security adviser Susan Rice said Tuesday – pointing specifically to Russia.

In a speech at a Center for American Progress Democratic forum, Rice, who also served as US ambassador to the UN for former President Barack Obama, issued a series of thinly-veiled warnings to President Donald Trump.

“We must ask, ‘What message are we sending now?’ Because, at this moment, our single greatest weakness – as a people, a country, and a global power – is our profound political polarization,” Rice said.

“Surely, we will often disagree. But, we sure as hell need to agree that a hostile foreign power has no business messing with our elections,” she said. “Because here’s the truth: If we cannot find our way to put country over party, and democracy over demagoguery, even in the face of such a dangerous external threat, then we might as well hang up our leadership cleats and resign ourselves to becoming a second-rate power.”

Rice also implicitly criticized the President’s frequent use of Twitter, saying that “we can’t allow Twitter wars to become shooting wars.”

Early in her speech, she declared that “bluster is for bullies.”

“Since I left the White House, I’ve become deeply concerned that the United States is squandering one of our greatest strategic assets – America’s leadership of the world,” she said.

Rice has been a target of Trump and his Republican allies in recent months. In April, Trump said he believed Rice committed a crime when she requested to unmask the names of Trump associates mentioned on intercepted communications during the Obama administration.

Asked by The New York Times if he believed Rice committed a crime, Trump responded, “Do I think? Yes, I think.”

Trump offered no evidence to support his belief that Rice had committed a crime, and Democratic and Republican congressional sources told CNN that Obama officials’ actions were normal and lawful. Rice has previously denied any wrongdoing.