I am not an international law specialist nor have I extensively studied the Israel-Palestine conflict, but I have written extensively about irredentism--the effort to enlarge one's country to include territories that are considered to be one's own by history and by blood. So, when I see pictures like this, I get engaged:
The river to the sea, used by either side, is an inherently irredentist phrase: that the lands between the Mediterranean and the Jordan River belong to just one side of this means seeking to get all of the territory of the other. Palestianians and their supporters have been saying this, and so have Israelis and their allies. Irredentism does not have to be this maximalist--Russia has claimed just a chunk of Ukraine. But these claims and efforts are inherently violent--that any effort to change one's boundaries to include territories governed by others will produce war because no country (or quasi-state) surrenders inhabited territory without a fight. Not Ukraine, not Taiwan, not Israel, and not Palestine.
The thing is: all territory has been occupied by multiple groups, so there will always be competing claims pretty much everywhere on the planet except perhaps Antarctica. Stuart Kaufman illustrated this nicely at the start of his book on Modern Hatreds:
So, if irredentist claims are possible everywhere, then why isn't there violence everywhere? Despite the news suggesting otherwise, ethnic violence, including irredentism, is rare. Ethnic conflicts do end, people do find a way forward without fighting. Remember that the key grievance between Germany and France for ... at least three wars ... was Alsace-Lorraine. Yet that is not an issue these days.
It is rare because irredentism is usually very self-destructive. It didn't work out so well for Nazi Germany and not so well for 1990s Armenia, Croatia, or Serbia. It has worked out well for China (Tibet), but Taiwan would be another story entirely. Bill Ayres and I compared the irredentisms that occurred in the 1990s (the aforementioned Armenia, Croatia, and Serbia) and those that did not--Hungary, Romania, and Russia. We confirmed that irredentism is very costly and self-destructive, but some countries do it anyway--when it benefits the politicians in power. What is good for the politicians may not be good for the public, which produced our title: For Kin or Country. Helping the kin abroad is often very bad for the country as war is bad. Russia is paying a pretty high price for its irredentist campaign against Ukraine, but, thus far, Putin hasn't paid a price himself.
So, when I see what is going on in Israel and Palestine, my bias is to watch the strategies politicians use to stay in power and see how that intersects with the nationalism of the country. Politics is in part about shaping the nationalism, defining the us, the them, and whether the them can be tolerated. A central irony we found is that the nationalisms that were more willing to include the thems, the others, in the state, the more able they are to engage in irredentism since any successful expansion will generally lead to more thems as well as us's in the larger state. Indeed, why do folks often oppose irredentism--a successful campaign would produce the equivalent of a massive wave of immigration, upsetting the balance of domestic politics. For example, a Greater Albania including Kosovo would likely weaken those who currently hold power in Albania since there are a lot of Kosovars.
And, yes, this gets to a key dynamic that the Hungarian case revealed--shades of identity, of us-ness. That for Hungarians in Hungary, they identify with the Hungarians outside of Hungary (due to the Treaty of Trianon in 1920) but only up to a point. Those Hungarians didn't experience post-1956 Hungary, so they don't have the same experiences and thus are not seen as quite the same. So, Hungarians in Hungary want the Hungarians outside of Hungary to do well but to stay put--they don't want to share power or their welfare state with them.
Anyhow, irredentism varies over time and over targets based on who matters to the politicians in power. Somalia's irredentism from 1960 to 1990 varied depending on who was in power and whose clans they needed for support. So, Somalia sometimes targeted all three neighbors, despite that being profoundly unwise, because the clans with ties to those in Djibouti, Kenya, and Ethiopia all mattered in the domestic political game. At other times, only those in Ethiopia matters (1976-1977).
Back to Israel and Palestine: the irredentist efforts of Hamas (it aims to eliminate Israel and govern the entire space) and of Netanyahu (his coalition includes many parties that seek to incorporate the occupied territories, hence the support for the crazed settlers)* reinforce each other, giving each set of politicians more support from those who fear the other. Not unlike Milosevic and Tudjman being each other's best allies as Tudjman could get Croats to support him because of the threat posed by Milosevic, and Milosevic could do the same to get Serbs to support him.
Have Hamas and Netanyahu delivered on other public policy issues? No, they are utter failures, but they are hard to replace when the enemy is at the gates. The coverage of this war has been quite clear that Netanyahu empowered Hamas to weaken the Palestinian Authority and perhaps also to keep the Israeli public focused on this than his own corruption.
So, what is good for the politicians--war--is bad for the public, but the publics go along with it because they don't see any alternatives. That people on both sides are talking about claiming territory from the river to the sea is understandable and horrifying, given what it requires--lots more bloodshed.
It empowers the worst leaders. It requires incredible leadership by alternative politicians to push in another direction. But until that happens, there won't be peace. BUT if that were to happen, you could have peace.
Alas, extremists have killed or marginalized the peacekmakers. So, things are going to be grim.
We did cover this a bit in the book when we survey the world's irredentist hotspots including Ireland, Kashmir, Taiwan, etc.
Anyhow, the focus should be on the politicians and their incentives. Irredentism is not inevitable, it can be sidelined. But it can be really hard to stop once it gets started because of the media it generates, the fear it generates, and how the two sides can reinforce each other's worst instincts.
*Yes, killing the two state solution is a key part of an irredentist strategy. Never really thought about that before, but two state solution inherently recognizes limits on expansion, so one must do away with that if one wants to add the desired territories.