On 9 December 1948, the former first lady of the US, Eleanor Roosevelt, stood up to address the recently formed General Assembly of the United Nations. The Universal Declaration of Human Rights (UDHR) - which would be adopted by the UN the following day - 'may well become the Magna Carta of our times', Roosevelt said, 'an event comparable....to the proclamation...of The Declaration of the Bill of Rights by the people of the United States'.
A Declaration rather a legally binding document - those would come later - the UDHR held the signatories to nothing more binding that a commitment to 'strive...by progressive measures, national and international, to secure their universal and effective recognition and observance'.
Despite this, the Declaration would lead to an entire global system of rules and regulations on human rights, backed up in many parts of the world by effective mechanisms to ensure they are observed and upheld.
The lack of a legally binding mechanism could have meant the whole project failed. But it didn't, and a key reason for this was that through the work of Roosevelt and others, and through the general commitment of successive administrations, the US threw its weight behind the UDHR.
Moreover, it took off as it did because the US had also thrown its weight behind many other post-war developments: the United Nations itself, the International Criminal Court and, a little later, the initial steps towards European integration - all became set in stone and seemingly unshakable in the post-war period because the world's leading super power put its shoulder to the wheel on this.
And just think for second off the context of the day: not only was the world by this stage cleaving into the camps of the Cold War, with an emerging nuclear standoff between the US and the Soviet Union but the world as a whole had just emerged from the internecine carnage of the Second World War.
To take a lead in overcoming both of these existential challenges, the US deserves enormous credit. Sure, like all super powers, it had its own interests at heart too: access to markets, the continued spread of capitalism (as well as resisting the spread of communism).
But nevertheless, to lead the project to turn around the 21st century from a first half based on unimaginable bloodshed, to a second half based on peace and progress was and remains a remarkable achievement.
Even just as an advert for liberal democracy and its strengths, it provided an enormous service to peoples around the world who strived and achieved freedom post-1945.
This is the real tragedy of Trump's withdrawal from the Paris Accord this week. The Accord itself, like the Declaration, makes no binding commitments on its signatories, beyond calling for parties to 'undertake and communicate ambitious efforts' on the articles of the agreement, whilst conceding that these will be a 'progression over time'. As such, nothing will change significantly right now in terms of the US withdrawal.
Moreover, as the Independent has pointed out this week, the real work of reducing our dependency on carbon is happening already, and will not be stopped by this move. There is much grandstanding here then from Trump.
However, it is the wider effects this grandstanding will have on international diplomacy that is the bigger tragedy here. What has happened to that great tradition of international leadership and diplomacy, no matter how flawed, epitomized by the likes of Roosevelt, Kennedy, and even Obama? To where do nascent democracies look to now for the lead example?
Further, what will it mean for an international community who have always relied on the political and economic might of the US to keep the shows like this on road? What will it mean for the climate change narrative itself? We have seen how Trumps disregard for the impact of his words has inflamed racial hatred in the US following his catastrophic attempt at a Muslim travel ban. Will the climate skeptics now be even more rampant in their denial of the science?
These questions will begin to play out, and soon.
Finally, what does this mean for us in the UK, especially in light of next week's general election? For all of us, this election now becomes just as much about collective survival - or at the very least, the survival of a meaningful international community to confront the global challenges we face, and crucially, the role of the UK in that community.
We must ask ourselves: are we happy that the UK was missing from a list of European nations who signed a declaration Friday to condemn Trump on Paris. We have to decide whether we are happy that senior members of the Conservative Party refused to criticize him, instead choosing to express 'disappointment'.
This matters for GE2017. This is not just about our own economy, or even just about Brexit anymore. This is now also about making sure we elect the right politicians who will stand up to the anti-rational, anti-cooperation, anti-human wave in Western politics that Trump represents.
And finally, perhaps most of all, this is an issue for voters under 25. The climate change threat is not really the problem of the over 65s, nor even the problem of those of us in middle age. It is, therefore, not an issue for the age groups that overwhelmingly voted for Brexit and for Trump will ever have to fully face. By the time the threat manifests in full, they will be gone.
So the question to the youth vote before the 8 June is now this: do you really want this largely male, pale and stale approach to Politics to shape the rest of your lives, and the lives of your children? Do you accept that decisions on climate change, the rights of women, the rights of minority groups in the West - all things that Trump has somehow assaulted - should be left in the hands of a generation who have lived the greatest era of peace and prosperity the West has ever seen and will avoid any impacts of the decisions they are now making?
Or do you think that the future is yours, not theirs?
If you do, go out next week and vote, not for the status quo, not for a hard Brexit, and not for a group of politicians who refuse to criticize the act of global vandalism we just seen across the pond. Whoever that means you must vote for instead is not the main point right now: what matters is that you do vote, now more than ever, and show your disaffection with those who currently hold political power.