Abbas has taken credit for Netanyahu's assurances of an imminent program to improve public safety in Palestinian communities - an issue high on the minority's agenda.
Netanyahu's office also recently sent an "official" letter to Abbas confirming plans for large-scale investment in developing Palestinian communities in Israel, allowing the United Arab List leader to claim credit for the initiative.
In fact, the plan was drawn up by Ayman Odeh, head of the Joint List, and negotiated not with Netanyahu's Likud party but with a Blue and White minister - part of Gantz's own cynical efforts to keep Joint List legislators onside in case they are needed in a later push to oust Netanyahu.
Return on investmentNetanyahu hopes for a long-term return on his initial investment in Abbas.
First he may need Abbas's four seats in his complex coalition arithmetic. If Netanyahu calls another general election - as he is expected to do to avoid implementing the promised hand-over to Gantz, the defense minister, next year - the United Arab List leader could deprive any rival to Netanyahu of the votes needed to oust the prime minister.
And second, Abbas could help Netanyahu either pass or thwart legislative moves related to his trial. Abbas could, for example, block efforts by Netanyahu's opponents to pass a law banning him from running for prime minister while on trial. Or if Netanyahu succeeds again in exploiting COVID-19 to postpone the legal proceedings against him, Abbas might help him pass a so-called immunity law exempting a sitting prime minister from being put on trial.
Abbas has shocked other Joint List members by hinting in interviews that he might consider voting in Netanyahu's favor on just such a law.
Abbas, meanwhile, has his own long-term incentives to cultivate this pact. There are already deep tensions within the Joint List that Abbas wishes to exploit for his own ends.
Ideological divisionsThe four parties making up the List share limited, if core, concerns about ending both Israel's abuse of the Palestinians under occupation and Israel's rampant and systematic discrimination against Palestinians living in Israel that severely degrades their citizenship.
The consensus on these issues has tended to overshadow the parties' very different, wider ideological positions.
Hadash is a bloc of explicitly socialist groups that emphasize class concerns they believe can unite Israel's Palestinian and Jewish populations. They have, however, failed dismally to draw poorer Jews away from supporting the right-wing populism of Netanyahu's Likud.
Balad appeals particularly to a new and aspiring secular middle class that wishes to advance social democratic values that clash with Israel's Jewish ethnic nationalism. That is one reason why, paradoxically, Balad feels the need to highlight its own community's Palestinian national identity, as a counterweight.
Abbas's United Arab List is a socially and culturally conservative Islamic party, but willing to horse-trade on issues that benefit its largely religious constituency. It tends to accentuate its "moderation", particularly after Netanyahu banned its chief rival, the more politically radical and extra-parliamentary Northern Islamic Movement, in 2015.
Finally, a faction under Ahmed Tibi, a former adviser to Yasser Arafat, operates as a more charismatic party, tending to cherry pick policies - and voters - from the three other parties.
Lower votes thresholdNone of these parties wishes to be in the Joint List, but they have been forced into an uneasy alliance since the 2015 election by the actions of Avigdor Lieberman, who was then a minister in Netanyahu's coalition.
Shortly before that election, Lieberman advanced the so-called Threshold Law on behalf of the Israeli right. It lifted the electoral threshold - the point at which parties win seats in the parliament - just high enough to ensure that none of the four Palestinian parties could pass it.
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