For the first time in eight years, Iran's supreme Islamic leader Ayatollah Khamenei led Friday's prayers in Tehran. It's being called a sign of how much pressure the regime is feeling since the US airstrike killed Iran's terrorist mastermind and US sanctions began crippling the Iranian economy.

Khamenei blasted Western countries in a fiery speech, accusing "American clowns" of trying to jab a "poisoned dagger" into Iran's back.

Now with sanctions ratcheting higher and Iranians protesting in the streets, some people wonder if this could be the moment the Iranian regime will finally fall after decades of oppressive rule.

Reza Pahlavi, the son of the former Shah of Iran, spoke this week at Washington's Hudson Institute about the conditions in Iran.

"I think people smell the opportunity for the first time in 40 years this time. Very different than 2009, even very different from 1997," Pahlavi said.

"The people have had it. Today's generation of young Iranians will not take it anymore. They want to have an opportunity for a better future. They want to be on the path of modernity and freedom. The only thing that stands between them and the free world is this regime."

CBN Middle East Bureau Chief Chris Mitchell says prayer is being seen as critical at this juncture.

"It's vital and it's pivotal really," Mitchell says. "There's one example I can cite: Dick Eastman, he's the head of Christ for the Nations. Back in 1987 he felt the Lord told him to go to the Berlin Wall and put his hands on hit and say five words: 'In Jesus' name, come down."

"There were many other people praying in the Soviet Union and around the world, but prayer is pivotal. Back there in the Soviet Union days and today now in the Islamic Republic of Iran."