Last week, Britain's former prime minister broke another promise - honestly, we've lost count of these - by announcing he would be retiring from politics.
David Cameron, who will be remembered as the United Kingdom's Conservative Party leader who needlessly took the country out of the European Union, resigned as prime minister on the morning that this referendum decision was announced in late June.
But now, with the country still reeling from this historic decision and with the Conservative government evidently still clueless as to how to actually enact it, Cameron has quit the political stage altogether.
The fact that he took such a big gamble with his own country, which he claims to love, overshadows other errors - although it inevitably is informed by other calamitous policies he initiated, too.
The EU referendum was a political decision, intended to assuage the right-wing of Cameron's own Conservative Party, and cauterize support for the Eurosceptic, right-wing populist UK Independence Party, or UKIP.
On the day Britain decided by 52 percent of the vote to quit the EU, Manuel Lafont Rapnouil, the Paris head of the European Council on Foreign Relations, observed that it wasn't Cameron's decision to call the referendum that astonished EU member states; no, it was the idea that he was not better prepared to win it.
Indeed, Cameron's Conservative Party, which managed to persuade only 39 percent of its voters to remain in the EU, was perhaps the least equipped to make the case for the EU.
Much like those of one of his predecessors, Tony Blair, Cameron's foreign policy errors carry an air of arrogance, self-interest and miscalculation, with terrible and far-reaching consequences.
Having bemoaned the constraints of the Union and having rallied against immigrants - though he is not, to be fair, the only European leader to do so - at a time when Europe desperately needed a unified approach to the migration crisis, Cameron couldn't credibly morph into a EU cheerleader.
But it was deeper than that: the inequality and hardship that Cameron not only presided over but actively exacerbated in the UK - food banks, zero-hour contracts, a starved welfare state, the list goes on - made the referendum impossible to win.
For people who see the EU as the cause of their neglect and poverty, Cameron could hardly say that, actually, that wasn't because of the EU so much as the ideological and ravaging austerity cuts that formed a core plank of his government's domestic policy.
Miscalculation on all fronts
This lack of planning and forethought was similarly on display in his decision to invade Libya in 2011.
Days after he stepped down as a backbench MP, the British Foreign Affairs Select Committee found that military intervention in Libya was "ill-conceived" and lacked a coherent strategy - holding Cameron "ultimately responsible".
|Cameron, second left, and French President Nicolas Sarkozy, fourth left, are greeted by the National Transitional Council head Mustafa Abdul Jalil, between them, and pro-NTC combatants as they arrive at the Tripoli Medical Centre in September 2011 [Reuters]|
Having intervened to remove Libyan dictator Muammar Gaddafi on the basis of insufficient information, Britain and France lost interest in the country, leaving the political and security situation to deteriorate.
Inevitably, Libya quickly descended into violence and lawlessness, creating the optimum conditions for the Islamic State of Iraq and the Levant (ISIL) to take root.
On top of which, the violence spread beyond Libya, quickly devastating Mali as well as spilling out across Africa and the Middle East - enabling and strengthening al-Qaeda in the Islamic Maghreb, which regularly launches terror attacks in the region.
The security vacuum in Libya has also meant that migrants as well as weapons can more easily be smuggled across the Mediterranean and into Europe.
So, in a terrible chain reaction of events, Cameron's actions in Libya helped create exactly the kind of instability that resulted in a surge in refugees, hostility to which was then manipulated to fuel the Brexit vote.
When, earlier this year - months before Brexit - US President Barack Obama described the Anglo-French intervention in Libya (or more accurately, its aftermath) as a "shitshow", his frustration with Cameron - whom he described as failing to rebuild Libya because he was "distracted by a range of other things" - was barely disguised.
This sense of frustration at Cameron's recklessness will doubtless be shared by leaders across Europe, knowing that Cameron, never a real team-player in project Europe, has now seriously jeopardised the future of the EU.
Much like those of one of his predecessors, the former Labour Prime Minister Tony Blair - whom Cameron cites as a role model - Cameron's foreign policy errors carry an air of arrogance, self-interest and miscalculation, with terrible and far-reaching consequences.
But Cameron, much like Blair, will never materially feel the devastating consequences of his mistakes.
A former PR man from the most privileged section of British society, Cameron has a memoir in the pipeline and, almost certainly, some preposterously well-paid gigs on the speaking circuit in the works, too.
If the penance for his political errors is leaving parliament, the lucrative engagements and handsome financial rewards now awaiting him will surely soften the blow.
Rachel Shabi is a journalist and author of Not the Enemy: Israel's Jews from Arab Lands.
The views expressed in this article are the author's own and do not necessarily reflect Al Jazeera's editorial policy.