Iran protests feel different, ‘almost populism on the move,’ says former NATO commander

Ben Stansall | AFP | Getty Images

Protesters gather outside the Iranian Embassy in central London on January 2, 2018, in support of national demonstrations in Iran against the existing regime.

The protests are the boldest challenge to Iran’s clerical leadership since 2009, when a disputed presidential election prompted millions to take to the country’s streets to voice their anger. The reformist protests — often referred to as the “Green Movement” — were ultimately crushed by the state.

Stavridis said the unrest presents both a challenge and an opportunity for the Trump administration.

“The challenge is getting the messaging right,” he said. “The opportunity would be to see the end of this ayatollah regime. Too soon to tell, but this one feels different.”

So far, the Trump administration is on point, as long as the statements are on the side of the people and not about overthrowing the regime, Stavridis said.

However, what’s really important is that U.S. allies get involved.

“We don’t want the United States to be the lone voice here because that will create the lightening rod that could undo the beginning of this protest,” Stavridis warned.

— CNBC’s Sam Meredith and Reuters contributed to this report.