It's been six months since Hamas militants invaded Israel, and Joe Biden has been that country's staunchest ally.

But this week, for the first time, his public support for Israel's campaign against Hamas is wavering, and his frustration boiled over in a tense call with Benjamin Netanyahu.

Is this a turning point for the U.S.-Israel alliance, or just a passing episode in Biden's dysfunctional relationship with the Israeli prime minister?

Joining me tonight to discuss this and more, Leigh Ann Caldwell is an anchor at Washington Post Live and a co-author of the Early 202 Newsletter, Francesca Chambers is a White House correspondent at USA Today, Nancy Youssef is a national security correspondent with The Wall Street Journal, and Peter Baker is the chief White House correspondent for the New York Times.

He is also the recipient of this year's White House Correspondents' Association's Award for excellence in presidential news coverage under deadline pressure.

Peter, another shiny piece of hardware for your bulging trophy cabinet.

Congratulations.

I don't think they told you that part of the prize is that you get the first question on Washington Week.

PETER BAKER, Chief White House Correspondent, The New York Times: What's the second prize?

FRANKLIN FOER: You'll find out next year.

Take us inside this tense phone call between Biden and Netanyahu.

How feisty was it?

Who was angrier?

How did Netanyahu respond to Biden's anger?

PETER BAKER: Well, remember at the State of the Union, the president was caught on a hot mic talking with some congressmen.

He said he was going to have a come to Jesus conversation with Netanyahu.

Now, I don't know how you have a come to Jesus conversation with the head of Israel, but this may have been that moment, right?

Angry at the killing of those World Central Kitchen workers, he had a 30-minute call with Netanyahu that I think was unlike any of the other ones he's had.

In this case, he said to Netanyahu the first time that my support for you, as unconditional as it's been so far, now comes with conditions.

You have to do some things to help the people of Gaza in terms of humanitarian crisis, in terms of stopping so much of the civilian casualties, and do more in terms of the negotiations for a ceasefire with Hamas in order for me to stick on your side.

Now, he didn't directly say, I'm going to cut off military hardware.

That's the implication.

He didn't give him a deadline.

It wasn't that concrete, as I understand it, but he was very strident.

That was the term that was used with me this week, very strident in this conversation.

Netanyahu, for his part, knew what was coming, right?

And I think he was ready to kind of try to meet Biden halfway.

He says, look, okay, there are going to be some things I can do on the humanitarian front.

I'll announce them within a few hours, and he did.

By Thursday night, early Friday morning in Jerusalem, he announced an initial crossing opening for humanitarian aid, a port, and so on.

Whether this will -- that's not enough to satisfy Biden, according to the White House, but it may be the start, and we'll see where that leads.

FRANKLIN FOER: But just in the arc of this war and the arc of this relationship between these two leaders, what has actually changed this week?

PETER BAKER: Yes.

Well, it's not clear.

It is important to hear, and it is a change to hear the president say that it's not unconditional anymore, that you have to meet certain standards in order for me to continue to be your backer.

But without telling us exactly what the or else is, it's still a little fuzzy, right?

And you hear Democrats saying, wait a second, not far enough.

You got to be more specific and explicit on tying arms supplies to conditions or cutting off all together.

On the other hand, of course, if you're Republicans and Israel supporters saying, wait a second, now you're abandoning our closest allies.

You shouldn't be putting pressure on them.

You should put pressure on Hamas.

So, the president, you know, the question is how far he's willing to take this.

And we don't really know yet.

FRANKLIN FOER: Nancy, I want to just unspool some of the events of this week and just start with the attack on the World Central Kitchen convoy itself.

How did this happen?

Was this intentional?

NANCY YOUSSEF, National Security Correspondent, The Wall Street Journal: Well, very simply, the Israeli military has a sort of lower threshold for what it's willing to tolerate and at risk that it's willing to put civilians in.

You had a convoy of three vehicles, World Central Kitchen vehicles, at about 10:00 P.M.

The commander on the ground, a colonel, believes that he sees a man with a gun near that convoy, and they fire on that convoy.

The challenge is it's very different than we would see from the U.S. military, in part because they didn't confirm that there was a gun.

They suspect one person, shot seven.

And so it's clear that they are not willing to put their troops at the same level of risk in some cases that the U.S. is.

There's no indication in this case of Israeli troops nearby.

And so what they discovered is, of course, there wasn't a Hamas fighter.

And rather than going after people maybe affiliated with, which I think was a suspicion, they ended up killing seven World Central Kitchen workers and also, I think, raising the concern among other aid agencies, many of whom pulled out, which put the pressure on the administration and the Israeli government to find ways to get aid to 2.2 million people, because so much of that aid may not be there now because of the strike.

FRANKLIN FOER: Francesca, the initial White House response wasn't quite as blistering as this phone call.

It's kind of come and fits and starts.

It's been a bit of a journey.

Can you just walk us through the evolution of -- FRANCESCA CHAMBERS, White House Correspondent, USA Today: Right.

So, initially, it was, we're going to wait to see what this investigation says before we specify any of the steps that we want them to take.

But they said they wanted to be swift and that they also wanted to be thorough, comprehensive, and that they wanted this investigation to be public.

But when I press this week to ask what kind of accountability it is that the White House actually wants to see, they could not provide specifics or define that at all.

Then by a day later, you know that president had then spoken to Netanyahu, again, by that time, you hear the White House issuing a more forceful statement.

But this really riled progressives in the base of the president's party, because when you have the White House press secretary standing up at the podium saying that the president could not have been more vocal with his outrage and saying that her definition of that is the first three words of his statement were that he was outraged and that he was heartbroken, that just did not go far enough for members of the president's party who want to see him, as Peter was saying, at least cut off offensive weapons.

They're not saying defensive weapons, such as the Iron Dome, but they do want to see offensive weapons in terms of military aid cut off.

And, of course, now you've seen Chris Coons coming out and talking about being open to conditional aid.

You had Tim Kaine as well, another senator in the Democratic Party today, speaking out about this.

And so the president, when he has close members and friends, people he used to serve in the United States Senate with, talking to him, you have Jose Andres, who has an open line of communication to him, these things are clearly weighing on the president, and he's grappling with them at this time.

FRANKLIN FOER: So, Leigh Ann, just talk a little bit more about what's happened with the response of progressives and Democrats on the Hill.

Has Israel essentially lost them as a constituency for the rest of this war?

Is this really a turning point for them?

LEIGH ANN CALDWELL, Anchor, Washington Post Live: We're going to have to see.

But remember, still on the table is $14 billion worth of aid for Israel, military aid that has not been passed, that is stalled in the House right now because of Ukraine.

Go back about a month ago, even a little bit farther, the only people who were really anxious about giving Israel more aid was the squad, the most progressive, and Senator Bernie Sanders, who voted against this aid package in the Senate because of the funding for Israel and there weren't conditions placed on it and there was no guardrails around it.

Now, after what happened this week, that sentiment seems to be growing beyond just Bernie Sanders and the most progressive liberals in the House, and we're going to have to see where this goes.

You've had Senator Chris Van Hollen, who didn't vote against it, but who had been calling for conditions, and that sentiment is really growing.

But I will say, for a while now, there has been a lot of concern among Democrats on Capitol Hill about how Israel has been engaging in this war, and not many have expressed it yet.

But now I think that this is a turning point.

I'm not sure yet what's going to happen in practicality.

But Biden is also very aware of this because this is impacting him politically, too.

FRANCESCA CHAMBERS: Bernie Sanders at the White House this week, too.

FRANKLIN FOER: So, Peter, there were multiple big events that happened in the course of this war.

The second was that Israel attacked an Iranian facility in Syria.

And so maybe it was not the most opportune moment for Benjamin Netanyahu to alienate his super power protector in the region.

We've been talking on the show for months about the possibility of a regional conflict escalating.

Are we there?

Are we on the cusp of something like that right now?

PETER BAKER: Well, and we'll see.

We're hearing reports, of course, from U.S. intelligence officials that they are expecting Iran to respond, to retaliate against Israel as early as tonight, sometime this weekend.

We don't know what that would look like.

Nancy has maybe a better sense of that than I do.

But you're right.

I mean, obviously Netanyahu is counting on the United States, and that may be why he was eager in this phone call to begin, at least to look like he's placating President Biden for now, because he does want the United States on his side.

And if he does risk losing Biden, he's really by himself, right?

The Israel is left alone.

He doesn't want that.

It may be also that he hopes that this Iran threat, you know, takes some of the attention away from World Central Kitchen, from Gaza, and reminds people of the larger threat that Israel faces in the region.

It has a lot of enemies in the region and reminds some of those senators who have traditionally been supportive of Israel, don't like Netanyahu and what he's doing in Gaza, but that they do have an interest in Israel beyond that.

FRANKLIN FOER: Nancy, I just want you to weigh in on this because you've covered past moments where we've seemed like we're on the cusp of regional conflict with Iran that might draw the United States further into a dangerous situation.

What do those past incidents suggest about how this might play out?

NANCY YOUSSEF: Well, in the past, when we've had these kinds of strikes, for example, when the U.S. killed Soleimani, the Quds Force commander, Iran didn't use its proxies.

It attacked directly, from Iran attacked U.S. forces.

And I think what they're trying to do at the time is sort of strike this sweet spot where they show that they're retaliating, but not escalating.

We saw troops that were injured but not killed at that time.

And now they're talking about doing strikes on an Israeli site.

If past is any precedence, then we'll see maybe those buildings will be cleared right before the strike happens, and it will hit that same sort of balance.

The challenge is, what if there's a mistake?

And in the past, this was between Iran and the U.S., so we had some sense of what the response would be.

Whereas we don't know how Israel will respond to a retaliatory strike by the Iranians.

And so I think it adds to the instability and unpredictability of this threat that the U.S. has now warned of a possible attack on U.S. or Israeli targets in the region.

FRANCESCA CHAMBERS: If I could just add, you're hitting on a really important point as to why this has been a difficult decision for President Biden when you talk about conditioning the aid.

You know, John Kirby, the National Security Council spokesman, earlier hinted at this earlier today, that they're very concerned that Israel lives in a, quote/unquote, tough neighborhood, and that if you don't send them weapons, they're facing threats from the Houthis, from Hezbollah, from other actors in the region.

And he specifically touched on the Iranian proxy groups as well.

And so that is what has also contributed to why even as the president hears from members of his party and disagrees with Netanyahu, this is something else that's going on in the back of his mind as someone who, again, chaired Senate Foreign Relations Committee and just has a long history of supporting Israel.

FRANKLIN FOER: Yes, that's a very important point.