Former CENTCOM commander and Carnegie Endowment for International Peace senior fellow on Iran strike

WASHINGTON (CBS, KYMA) - Retired Gen. Frank McKenzie and Karim Sadjadpour spoke with Margaret Brennan on Face the Nation Sunday talked about the U.S. and Israel launching a strike against Iran.

According to President Donald Trump and Iranian media, Ayatollah Ali Khamenei was killed in an attack earlier Saturday.

When asked who the new leadership of Iran is, after President Trump said he's willing to talk to the new leadership, Sadjadpour, who is a senior fellow for the Carnegie Endowment for International Peace, said:

"I don't think that's even clear inside Tehran, who is the new leadership? You know, this is one of the most unpopular regimes in the world, and I'm skeptical that there's going to be anyone who is palatable for both the senior clergy, the Revolutionary Guards, and 90 million Iranians. There's probably no government in the world with a greater gap between its government and its people than Iran so I'm skeptical there's going to be any single figure who can immediately fill the enormous void of Ayatollah Khamenei."

Brennan followed up by asking Retired Gen. McKenzie, who is the former Commander of the U.S. Central Command (CENTCOM), if he agrees with Sadjadpour's assessment, and McKenzie said:

"I think we're still in the early stages of this campaign. There are several days of continued strikes ahead of us from [CENTCOM] and from Israel to reduce the Iranian ability to volley fire rockets at us. We'll see how that progresses in the next few days. The leadership targets have clearly had an effect, and I believe the loss of Iranian effective national level command and control is going to have a pernicious effect on their ability to wage this war. As to what might follow, whether it's civil war, a fractured state, don't know. Actually, for me, it's hard to see how it could be worse than what we had before."

CENTCOM posted to X Sunday saying three U.S. service members were killed in Operation Epic Fury.

In an update Monday, CENTCOM said one of the U.S. service members who was seriously wounded during Iran's initial attacks has died.

This prompted Brennan to ask McKenzie what the American public should be prepared for, and he said:

"The American people should be prepared for several more days of exchanges of long-range rockets. We're going to continue to strike them with our aircraft, with our TLAMs, our Tomahawk Land Attack Missiles, and the essential calculus over the next 72 to 96 hours is going to be whether or not we can reduce the Iranian ability to generate volleys. And by volleys, I mean groups of missiles that are fired at our bases in the region. It's hard for them to generate a lot of missiles at Israel because of the range and just for various reasons. But what we want to do is we don't want to let them fire large numbers of rockets at Al Udeid Air Base, for example, Al Dhafra Air Base, or the cities of our friends in the region, which they have done indiscriminately. So that's going to be a key thing to watch over the next 72 to 96 hours. CENTCOM has planned for this for years. We probably going to...we're probably going to take more casualties. I think the president's comments actually were spot on when he warned the American people that this wasn't going to be...it wasn't going to be a cake walk. I think he knows that, but I think you know, we're probably going to have more casualties before this is over. I hope we can certainly minimize those, and I know that our commanders in the region are doing everything they can to keep those numbers down."

During the interview, Brennan asked what Khamenei's death means for the Islamic Republic to have hime gone, and Sadjadpour said:

"He was the longest serving dictator in the world. For four decades, he reigned over Iran. For most Iranians, three quarters of whom were born after the 1979 revolution, he was the only ruler they ever knew. And I think this is a society...I would describe it as perhaps the most secular society in the Muslim Middle East, perhaps the most pro-American society in the Middle East. And people...Iranians, recognize they'll never fulfill their enormous potential as a nation so long as the ethos of their government is death to America and death to Israel. And so there's an enormous demand for a government which is perhaps not democratic, but puts national interests before revolutionary ideology."

To watch more of Brennan's interview with McKenzie and Sadjadpour, click here.