In their rather spirited debate last night, Hillary Clinton and Bernie Sanders had a lengthy exchange on Israel, and what we in the media usually do the next day is assess who got the better of the argument and who helped or hurt their cause. But in this case, that’s not really what matters.

Far more important is that their exchange widened, just a little, how we talk about this issue. And in the process, it demonstrated the value of Sanders’ candidacy. Even if he doesn’t win his party’s nomination, he’s doing a service to the public.

It’s been said many times that the debate on Israel within the United States is far more constrained than the debate on Israel within Israel. That’s particularly true within the Democratic Party, where the voters (even, or perhaps especially, Jewish voters) are far more liberal than the politicians who represent them. To simplify a bit, in debates about Israel, Republican politicians will say that Israel is always right no matter what it does, and neither the occupation of the West Bank nor any military action it takes can possibly be questioned. Democratic politicians, on the other hand, will emphasize that they are absolutely on Israel’s side, and though they will allow that the Israeli government’s settlement policy is problematic and they remain committed to a two-state solution, their criticisms of the Israeli government will be mild at best. If anyone asks about human suffering, politicians in both parties will be sure to bring up the people of the Israeli town of Sderot, who have been targeted in Hamas rocket attacks, and speak eloquently about how difficult it is for Israelis to live under constant threat of terrorism.

Missing from this conversation is any acknowledgement of the Palestinians — their own suffering, their rights, and the inherent value of their lives independent of what Hamas or anyone else does or advocates. So that’s what makes this part of last night’s debate notable. Here’s how it began:

BLITZER: Senator Sanders, you maintained that Israel’s response in Gaza in 2014 was, quote, “disproportionate and led to the unnecessary loss of innocent life.” What do you say to those who believe that Israel has a right to defend itself as it sees fit?
SANDERS: Well, as somebody who spent many months of my life when I was a kid in Israel, who has family in Israel, of course Israel has a right not only to defend themselves, but to live in peace and security without fear of terrorist attack. That is not a debate.
But what you just read, yeah, I do believe that. Israel was subjected to terrorist attacks, has every right in the world to destroy terrorism. But we had in the Gaza area — not a very large area — some 10,000 civilians who were wounded and some 1,500 who were killed.
Now, if you’re asking not just me, but countries all over the world, was that a disproportionate attack, the answer is that I believe it was, and let me say something else.
As somebody who is 100 percent pro-Israel, in the long run — and this is not going to be easy, God only knows — but in the long run if we are ever going to bring peace to that region which has seen so much hatred and so much war, we are going to have to treat the Palestinian people with respect and dignity.
So what is not to say — to say that right now in Gaza, right now in Gaza unemployment is somewhere around 40 percent. You got a lot of that area continues, it hasn’t been built, decimated, houses decimated, health care decimated, schools decimated. I believe the United States and the rest of the world have got to work together to help the Palestinian people.
That does not make me anti-Israel. That paves the way, I think to an approach that works in the Middle East.

The rest of the discussion is too long to reproduce here, but briefly, Clinton reiterated Israel’s right to defend itself and talked about her experience in dealing with Israeli and Palestinian leaders, while Sanders expressed his support for Israel while repeatedly circling back to talk about the Palestinian people and what they’ve endured. (Clinton did mention the rights of the Palestinians, but in a way that can only be described as perfunctory.) While I’d have to do some time-consuming research to be sure, I don’t recall ever hearing this much discussion about the Palestinians in a presidential debate, at least not a discussion that actually concerned their rights and needs.

And that, in a nutshell, is why Bernie Sanders’ presidential campaign has been so important, even if he doesn’t get the Democratic nomination. There have been candidates before who challenged the orthodoxy of their party or the range of policy options presented to the public. But none of them have been as successful as Sanders. Last night we saw him standing alone on a stage with the person who is likely to be the next president, pushing her to acknowledge something that neither she nor anyone else at the top levels of American politics is inclined to talk about.

That isn’t to say that Sanders should get nothing but praise on this topic. He did assert that he’s “100 percent pro-Israel,” but as I’ve argued before, the very idea of dividing people into “pro-Israel” and “anti-Israel” categories is the quickest way to short-circuit actual thought and debate on this topic. Last month, he declined to deliver a speech to the American Israel Public Affairs Committee, and instead gave a speech on the topic in Utah. While turning down their invitation may have been in response to the fact that AIPAC is essentially the Likud lobby, it was a mistake — had Sanders gone before the group and told them what other politicians won’t, it would have been front-page news everywhere and had a far greater impact. And just this week, he suspended his newly-hired Jewish outreach staffer after a conservative publication published an old Facebook post in which she said mean (and true) things about Benjamin Netanyahu.

So Sanders is not immune to pressure to toe an appropriate line on the subject of Israel. But in the debate, the discussion ended with Sanders saying, “we cannot continue to be one-sided. There are two sides to the issue.”

Unfortunately, this is still seen as radical notion, like any number of things Sanders has suggested. But it shows why the race is better for having him in it.