Retired Gen. David Petraeus defends the Trump administration's foreign policy during a national security panel at the Aspen Idea Festival. (The Aspen Institute)

During a national security panel at last week's Aspen Idea Festival, retired general David Petraeus offered what the panel's host labeled perhaps the most robust defense of the Trump administration's foreign policy yet.

Then Petraeus was asked about Trump personally, and things took a turn.

As political affairs scholar David Rothkopf noted in an op-ed he wrote for The Washington Post on Tuesday, he asked Petraeus — after Petraeus argued that Trump had surrounded himself with a solid team that was instituting a measured, continuity-based foreign policy with plenty of successes — whether Trump himself was fit to serve as president.

Petraues's response was decidedly not “yes.” Instead, he said Trump's fitness for the office was actually “immaterial.”

I went back to the video to see if some context was missing from Rothkopf's op-ed. There isn't: It's as damning as it sounds. Here's a guy whom Trump considered nominating for secretary of state putting a pretty good face on the Trump administration — and then being unable to say whether the president is a mentally fit commander in chief.

The exchange:

ROTHKOPF: But that’s the question, and let me ask you guys that directly. Julia [Ioffe]’s addressed it directly. I talk to lots of world leaders, traveled around. I can’t tell you, in all of my life doing this, it never once came up — the question whether or not the president of the United States was fit to serve and whether or not the president of the United States was actually mentally ill. And in the course of the past six months, it’s come up every couple of days from senior leaders around the world. Do you think the president of the United States is fit to serve as president?

PETER FEAVER: General Petraeus? [LAUGHTER]

PETRAEUS: Thank you. As I used to say in uniform, that sounds like a policy question. [LAUGHTER] And look, I think it’s immaterial. Again, what I’m focusing on is the team. [GROANS] No, I —

ROTHKOPF: Give him a chance to explain.

PETRAUES: Let me explain. You know, pronouncing yes or no, I don’t think that changes a darn thing. What I’m pointing out is that around him, he has a very good team. They’ve been slightly tested a few times — I think the use of chemical weapons was one of those -- and I think they did better than was done the last time, when there was an explicit red line already in existence, stated on multiple occasions. Again, I think a lot of the policies that had been pursued so far -- look, there’s all kinds of discordant stuff. Bibi Netanyahu’s sitting there, and the president says “one state, two state, eh, whatever they want.” We’re back to the two-state solution. Again, I talked about China. We’re back to the One China [policy], and we actually have strategic dialogue. By the way, I don’t think it is at all bad that a president of the United States talks to another leader -- even if that leader has many conflicting objectives -- at all. I believe Henry Kissinger said that you should have strategic dialogue with your adversaries.

This is a dance that many a Trump defender has been forced into — arguing that things aren't as bad with Trump as some would have you believe, and then punting when being asked to vouch for Trump personally. The latter is a much more difficult thing to do, because it means you are attaching your expertise to Trump's unpredictability and whatever he might do in the future.

But it's also important to emphasize just how low a bar this is. The fact that Petraeus can't even say that Trump is a fit commander in chief speaks volumes. And Petraeus seemed to be going out of his way on the panel to argue that U.S. foreign policy and national security are on the right path. He said repeatedly that we shouldn't get bogged down in Trump's “discordant” tweets and public comments and should focus on actions.

Here's a taste:

Follow the money, and follow the troops; follow the decisions. Don’t necessarily always follow the tweets. You do need to listen to them, you need to read them, but, again, it’s about what is actually happening. This is a president who, when Bashar al-Assad used chemical weapons on his people, did not temporize. Within 36 hours, there were 50 or so cruise missiles that hit. It was measured. It was deliberate, pointed and so forth. And when it was threatened this time, I think Bashar al-Assad took note of that. It’s hard to say whether it absolutely deterred something that was in the works or not, but that’s how you build American credibility — building, I think, effectively on the work that was done in the previous administration in the fight against the Islamic State, prosecuting that well. ...

So, again, you just take issue after issue, there’s a devolution of responsibility that I applaud — again, in part because I have such confidence in the national security team. There’s not micromanagement of troop numbers, yet the troops numbers aren’t ballooning. And so I think it’s actually going forward in a very measured manner and, again, much more continuity than change. You had lots of disruption. You had a phone call from the Taiwanese president [which ran counter to longstanding U.S. policy toward China], but ultimately the president adopts the “One China” policy, embraces it, invites President Xi, has a relationship, and now there’s four working groups established that are working together so they can address the core issue of North Korea and the other challenges. Certainly missed an opportunity at NATO headquarters when the 9/11 memorial was unveiled, reminding us that that was the only time that Article 5 was ever invoked was after 9/11, and we did not step up at that moment and guarantee the Article 5 collective self-defense [clause]. But ultimately we’ve done that, have reassured our alliance partners in the Far East. So again, I think a good bit more continuity than might be expected if you just, again, read different tweets or statements to the press. ...

I think the problem here is actually distilling out the discordant comments to the press, the tweets — you name it — and actually trying to focus on what is going on. … Look, there are lots of things here about which one could wring his hands. There are also things that I actually am happy to see. I don’t think this is a president who is going to announce a surge of forces and in the same speech announce a drawdown date, regardless of the conditions on the battlefield. So let’s keep that in perspective, even as you may or may necessarily applaud, again, all the communications.

Even in these comments, the argument from Petraeus seemed to be that Trump himself can only do so much damage and that the people around him would keep him in check — implying that Trump was, to his credit, allowing them to keep him in check. This is what some of Trump's biggest critics have hoped would be the case, and Petraeus suggested their wishes were coming true.

Then he was offered the chance to come out and say what he really meant. His nonresponse spoke volumes.