The following is a transcript of an interview with retired Gen. Frank McKenzie, former chief of U.S. Central Command, that aired on Feb. 4, 2024.

MARGARET BRENNAN: For some analysis on the situation in the Middle East, we turn now to the former head of U.S. Central Command, General Frank McKenzie. He was in charge of U.S. forces in the Middle East for three years under the Trump and Biden administrations. Welcome back.

GEN. FRANK MCKENZIE: Good to be here, Margaret.

MARGARET BRENNAN: General, how would you assess the impact of the strikes so far, which you just heard National Security Advisor Sullivan say is just the beginning?

GEN. MCKENZIE: I- I think that's pretty accurate. I don't think we know yet. I think it's going to require more work. And I think we do need to have an understanding of what we want as an end state. For- for me as the operational commander, back when I was in command, it would be that they cease attacks on our bases and- and operating positions in Iraq and Syria. That's a pretty clear end state. You know, the problem is, there's a lot of talk about Ira- Iran actually not giving the order for this specific attack. And there's some truth to that, because around 2020, Iran began to give blanket clearance to these groups to attack United States positions in Iraq and Syria. So they now operate under a- a sort of procedure where there's no mother may I, they have the opportunity to generate these attacks without directly going back to Iran. And while Iran is certainly ultimately complicit because they provide the weapons, they provide the training, they provide the funding, in some cases they probably provide some targeting assistance, it's hard sometimes to find that track back for a specific attack, because of the way Iran has ingeniously designed their command and control process.

MARGARET BRENNAN: That is important context on the question of whether they have control or not. You, before this devastating attack that killed three American service people, you were on the record in a Wall Street Journal editorial, saying the U.S.- you referenced the President saying the U.S. doesn't want to escalate and you said, "Unfortunately, it is the U.S. that is being deterred, not Iran and its proxies. To reset deterrence, we must apply violence Tehran understands." What would that look like?

GEN. MCKENZIE: Margaret, and I- I first of all, I still stand by those words. I think this particular campaign we're on, we've done two things that I think undercut us. First of all, there's a continual reference in our policy statements about not wanting to escalate. Look, I agree, escalation is dangerous. But if the greatest fear is escalation, we should leave. We can reduce the danger of escalation to zero if we leave. Clearly, we have higher priorities than preventing escalation. So we- we should recognize that. The second part is, we have explicitly taken Iran itself off the list of potential targets in this campaign. I am not advocating for striking Iran. I am advocating that they need to be in the space of possible targets, so that they- so that they're held at risk. What happens when we say, well, we're going to strike targets in Iraq and Syria, we're not going to strike targets in Iran, at least kinetically, targets in Iran, that gives them aid and comfort. That's not a good thing to do. And what we want to do is induce in their minds and their cognitive space, a concern about continuing on this path and what it might mean to them. Look, Iranian foreign policy is built on three things. It's built on preservation of the theocratic regime, number one, above all others. Number two, the destruction of the state of Israel. Number three, the ejection of the United States from the region. Number one is a point of strength for them, but also a point of weakness. And I believe we are consciously neglecting it in this campaign. 

MARGARET BRENNAN: Four years ago, they were forces under your command who killed Iran's Quds Force Commander Qasem Suleimani, when he was in Iraq, from Iran. His successor doesn't seem to be quite as influential and there are some pointing to the leader of Hezbollah now as choreographing the militias. Is this the outcome you expected when the Trump administration decided to take Suleimani off the battlefield?

GEN. MCKENZIE: Well, Margaret, it's important to understand, we took Soleimani off the battlefield because he felt- we felt he was preparing an imminent attack on the- on our embassy and other locations in the Middle East. So certainly, there were long term considerations, but he was a clear and present immediate danger, and we took steps to- to- to remove him from the battlefield because of that. Now, what's developed after that, you're right, the- the IRGC Quds Force has not been able to get into Iraq and bring people together as Soleimani was, because his successor is a much weaker military leader than- than Soleimani. I- it's unclear to me that- that Nasrullah, the leader of Lebanese Hezbollah, is filling that space. I think the most interesting thing about Lebanese Hezbollah and Nasrullah is the fact he has not chosen to engage in large scale conflict with Israel right now, because of what's going on down in Gaza. And I think that's- that's important to look at. It's like the dog that didn't bark in the night. That can be important. He's instead chosen to hold- hold back, to observe the situation. And I think that's an important thing that we should continue to- we should continue to take a look at, because they're the largest non-state military entity in the world, with thousands of weapons that could cause great pain to Israel. On the other hand, Israel has vast resources they could apply against Lebanese Hezbollah, should this war ensue. And I don't think LH wants that war. Now they may be- they may be influencing events in Syria and Iraq. That's just not known to me at this time. I think it's more of a hodgepodge of efforts there. But I do believe ultimately, Iran is clearly behind it.

MARGARET BRENNAN: U.S. intelligence estimates Israeli forces have killed about 20 to 30% of Hamas fighters since October, that is far short of destroying Hamas. How would you judge the level of success of Israel's campaign?

GEN. MCKENZIE: It's very limited so far. You know, I think they set themselves a goal of removing the political echelon, and the military leadership echelon of- of Hamas, when they went in. They have not been successful to date at doing either. And these campaigns are nonlinear. So you don't necessarily go from day to day, you could have a big breakthrough here. And things could change suddenly on the ground. But I think the larger issue, at least for me looking at it is, you have to have a theory for what it's going to look like when it's over. You know, what's- what- what's going to happen in Gaza, and we've had some people that have talked about it earlier on the show today. And I think it's important to consider that. You need- you need a vision of an end state when you begin a military campaign, because everything you do then subtracts or adds to your ability to get to that point. And I would argue that needs to be something like a two state solution. You're gonna need help from the Arab nations in the region to go in there and- and do something in- in Gaza. I think Israeli occupation would be the least desirable of all outcomes.

MARGARET BRENNAN: General McKenzie, thank you for your expertise. We'll be back in a moment.