The slow crumbling of Netanyahu’s political prestige reached its nadir on Tuesday, when his own heir apparent Gideon Sa’ar turned against him to elevate arch-rival Reuven Rivlin to presidency.

Reuven Rivlin’s victory in the presidential elections on Tuesday was a resounding one, but nowhere near as resonant as Benjamin Netanyahu’s defeat – a domestic political defeat to match his 2013 failure to stop Iran-U.S. rapprochement, which yanked the rug out from under his foreign policy.

Rivlin and Netanyahu weren’t running against each other. Quite the contrary, Rivlin was the candidate of Netanyahu’s own party, Likud, adored by the party’s rank-and-file and Israelis in the street alike. With a bit of self-discipline and an exercise of that most elusive quality of leadership – humility – Netanyahu could have transformed today’s event into a sweeping victory for his party, for the nationalist camp and for himself personally. Worst come to worst, he could have even written it off as a pointless formality, playing on the public’s weariness of the largely ceremonial presidential role. Instead, Netanyahu made it into a personal crusade, raising the stakes of the presidential race immensely and amplifying his defeat to match. He is perceived as having ignored, deceived and ultimately betrayed his own party – and all to lose the race. This doesn’t mean Netanyahu will be going anywhere tomorrow, but it does mean that the historical fourth term he covets is becoming increasingly unlikely, and that like many a Prime Minister to have served three terms, the final blow might well come from his own home party.

The Netanyahu-Rivlin rift goes back to 2009, when the freshly victorious Netanyahu had Rivlin elected once again as Speaker of the Knesset. Rivlin, a tradionalist if there ever was one, soon proved to be much more loyal to parliament and to the letter of the law than to his own party. He stalled nearly every piece of anti-democratic legislation that came his way, deferring votes, sending bills to die in committees and even setting up committees especially to kill those bills he felt impinged on democratic rights. Along the way, he protected MK Hanin Zoabi when the Knesset tried to sanction her for taking part in the Gaza flotilla; elevated MK Ahmed Tibi, the Palestinian Israelis most love to hate, to deputy-speaker; acknowledged the “great suffering and real trauma” endured by Palestinians in 1948; and called for the establishment of one state in all of historical Israel-Palestine, where Palestinians would also have the vote.