Pity Prime Minister Benjamin Netanyahu and U.K. Labour Chair and Opposition Leader Jeremy Corbyn. Both politicians, seemingly at the height of their power should, in theory, be well placed to emerge victorious if elections were to be called in their respective nations. With no discernable rivals in either the left or right wing camps currently posing a threat to his continued rule, Netanyahu could easily collapse the government and coast to a comfortable victory, changing only the substance of his coalition. Likewise, Corbyn and the Labour Party have found themselves advantageously poised to win control of the government in the wake of an incoherent Brexit policy being pushed by Prime Minister Theresa May, a divided Conservative Party, and a fight over possible succession.

But both leaders have made a series of terrible missteps in the last few weeks: Netanyahu’s decision to push for the already divisive Nation-State Law just before the summer recess deeply divided Israel (possibly the prime minister’s objective) and  alienated large swathes of Israeli Druze, a “model minority” community not known for its political activism against government policy, calling into question Bibi’s hold on the right-wing electorate and the cynicism of his legislation. Likewise, Corbyn’s insistence in avoiding full adoption of the IHRA definition of anti-Semitism have made his already controversial views on Israel even more suspect, and destroyed what little clout he had left among Jewish voters. What’s more, both of these politically disastrous situations were self-inflicted and completely avoidable.

Attempts to equate Bibi and Corbyn as individuals are difficult without trying to make facile comparisons that may sound interesting on paper, but have no bearing in reality. Netanyahu has achieved great personal success in his political career, winning the premiership four times (thrice consecutively). Corbyn is head of the largest opposition party. But both are inflicting similarly significant damage on their respective internal party infrastructures that will continue to reverberate long past their own retirement. It’s difficult to ignore, at this juncture in their respective political careers, the success that each man has had in entrenching a mythic-like status around himself. But cults of personality are always double-edged swords (when they’re not, in retrospect, terribly harmful to politics) to those who initially benefit from them. The mass of adoring fans who believe you can do no wrong also prevents the need for any sort of introspection, which can prove deadly for your ambitions down the line, and worse, to the very cause for which you advocate.

Indeed, the tendency for Netanyahu and Corbyn in the face of harsh criticism of this sort has not been to step back and conclude they’ve erred. It is to double down, turning long-time reliable allies who dare to step out of line, into untrustworthy traitors. Who could predict that the Druze, only weeks ago held up as a paragon for integration and with many reliable supporters on the right, could suddenly invoke the wrath of the prime minister and his inner circle who dismissively assert they should “go to Druzia?” Of course, one need only be reminded of the pandemonium brought about by actress Natalie Portman’s decision to refrain from appearing alongside the prime minister at the Genesis Prize ceremony, transforming her overnight from Israeli darling to covert BDS activist. Amongst the Corbynite true believers, even those closest to the Labour leader, like party deputy leader Tom Watson (who recently declared that the party had to tackle the accusations of anti-Semtism full on), have been summarily attacked.

Netanyahu, unlike Corbyn, seems to have made peace long ago with the fact that his transformation of the Likud — never a “small l” liberal party to be sure, but one that at least aspired to a modicum of liberal democracy — has driven away many moderate Israelis. This has been Netanyahu’s modus operandi for years. Yet Corbyn’s self-image as an anti-racist crusader seems to have made him blind to the damage he continues to inflict. It’s difficult to tell which of these — naked cynicism or zealous adherence to ideology — is worse. Yet the results lead to the same place: an increasing unwillingness to brook dissent because it seemingly distracts from the immediate victory at hand.

But as Ha’aretz columnist Anshel Pfeffer recently pointed out, the actions of an individual or group can greatly affect the brand of that particular entity negatively in the long run even if short term gains seem favorable to their position. Die-hard Corbyn followers’ determination to bring about an imagined economic revolution means they’ve willingly rationalized not only his inability to take the fears of the Jewish community seriously, but embraced the rest of his political baggage, which is considerable. This includes his vocal support for the IRA, his defense of Chavismo and his silence in the face of Venezuela’s current economic and humanitarian distress, his many appearances on the Iranian state-owned propaganda network PressTV, his past antipathy towards both NATO as an organization and desire for British nuclear disarmament, and his acquiescence to Russian President Vladimir Putin’s bad behavior across Europe.

Corbyn now risks, through his actions, conflating his own personal brand of what he deems progressivism with that of the broader West’s, and a Labour electoral win could give an impetus for other far left-wing parties to do the same. The result of this could prove disastrous for the left aisle of British politics, in both the short and long term. Regardless of their dislike of May and the Tories, a wary electorate might come to view the prime minister as the lesser of two evils until Labour manages to expunge the radical elements that have currently overtaken its party apparatus. In the long run, the results may have far more damaging effects. A theoretical Corbyn government—in some ways, the leftist mirror image of a Trump administration that throws all caution to the wind, going against decades of conventional centrist policy—might wreck such havoc on Britain, both domestically and internationally, tainting the party for the foreseeable future and making Labour a toxic brand synonymous with extremism.

In Israel, as is to be expected, the stakes are even higher. Netanyahu’s brand of politics had long ago pervaded — and many people might say, poisoned — Likud’s core identity to the point where long-time members have either been sidelined and stripped of any meaningful power, or fled to more ostensibly moderate parties. Yet Netanyahu’s divisive, paranoid style has not stopped at the boundaries of his party. It has leaked into the politics of even those center-right parties like Kulanu, allowing figures like Finance Minister Moshe Kahlon to rationalize voting for problematic legislation and continuing to act as the moderate mask of a nationalist coalition. It has continued to seep outward, implicating the government, the entirety of the state and its citizens, and in some cases, the very legitimacy of the Zionist enterprise. However unfair it may be — and to be sure, the standards Israel are held to are often frustratingly unrealistic — Netanyahu’s actions and his routine conflation of his own rule with that of Israel’s standing in the world will continue to diminish.

There is, of course, still time for both Netanyahu and Corbyn to change course, apologize for the mistakes they’ve made and, in theory, attempt to rectify them. Given their past track records, however, it’s far more likely their narrow-minded tunnel-vision will continue to guide them in a direction likely to inflict ever greater offense. How that will affect their electoral fortunes going forward is hard to say, but it’s safe to assume that neither one seems capable of turning around when victory seems so near.