Only three people have ever really understood the Schleswig-Holstein business: the Prince Consort, who is dead; a German professor, who has gone mad, and I, who have forgotten all about it.
ord Palmerston, 19th Century British Prime Minister, on the Schleswig-Holstein Question.
When he gets the chance, Leo Varadkar is known to make time in his schedule for some mindfulness meditation - the bringing of one's attention to experiences occurring in the present moment.
And there may well be no better time than this weekend for the Taoiseach to luxuriate in the moment. With what he described as a 'bulletproof' deal to prevent a hard border in his pocket and buoyed by an 11-point lead over Fianna Fail in the Ipsos-MRBI poll, Varadkar departed the EU summit having exerted greater influence on European statecraft than any previous Taoiseach.
As Financial Times commentator David Allen Green summed it up, "the Irish Government currently has more practical power over the UK's future trade policy than Britain's own ministers, legislators and voters."
This too will surely pass, but fortunately for Varadkar our politics live only for the present moment. And while the media likes to back a winner, it was still remarkable to witness the speed at which previous critics were out of the traps to shower praise on the Taoiseach. Oliver Callan, in particular, described Varadkar as "an unstoppably popular Taoiseach".
It was unclear whether it was Varadkar's performance on Brexit or his decision to cop the flak about the Frances Fitzgerald affair on Marian Finucane that swung it.
What is irrefutable is that Brexit, which has already laid waste to a generation of British politicians, will be the making or breaking of Varadkar and his government. While some dismissed Fine Gael's 11-point lead as an aberration, in reality, it reflects a trend that has been bubbling under in private polling since Varadkar succeeded Enda Kenny.
Brexit has become the most salient issue for voters, the main lens through which they are judging the performance of the parties and their leaders. For all the supportive noises from the opposition, only the Government is in a position to do anything meaningful about the issue. This has given the Taoiseach and his new Tanaiste, Simon Coveney, the opportunity to show leadership on a matter of profound importance from the start.
The electorate clearly approves of the more robust approach to negotiations since Varadkar became Taoiseach. Furthermore, as all parties in the Dail support the Government's approach to Brexit, there is no real scope for the opposition to inflict meaningful damage on Varadkar on the issue that matters most to voters. And if the collective shrug of the electorate's shoulders about the events surrounding the resignation of Frances Fitzgerald is any guide, it may well be that for the time being, no other issue can shift the aura surrounding the Taoiseach that he is the man for the hour.
And yet, something lingers from the Fitzgerald affair that should give pause for thought. While Varadkar made a virtue of not going by the normal rules in his refusal to throw his Tanaiste under a bus, he ultimately overplayed a weak hand.
In politics no more than in poker, knowing when to fold and walk away is critical to survival. When that moment arrived, the Taoiseach displayed a worrying insouciance. It is crucial that he doesn't repeat the mistake in taking the assurances of his EU colleagues at face value as we move into the business end of the Brexit negotiations.
The fudge on the Northern Ireland border that enabled the Brexit negotiations to move on to the next phase is held together by a deliberate ambiguity of language, which reveals the full extent of the British government's double-think.
There can be full regulatory alignment between both Ireland and Northern Ireland and between Northern Ireland and Great Britain - and at the same time the United Kingdom as a whole will leave the single market and customs union that underpins this alignment.
In truth, like the Schleswig-Holstein question of old, there may be no one in Europe who really understands or even wants to understand the fudge contained in the so-called EU-UK Joint Report. And as we have seen from David Davis's backsliding this week, and Michael Gove's suggestion that it could all be reversed after an election - undoubtedly with him as Prime Minister - it means fundamentally different things to the Taoiseach and the Brexiteers.
Gove is said to have agreed to support the deal on the Irish border only after receiving legal assurances that it would not prevent Britain diverging from the EU post-Brexit. The Brexiteers in the Cabinet are determined to hold May to her promise to depart the single market and customs union. For them, the litmus test for Brexit is that the UK has full regulatory freedom once it has left the EU. Contrary to Varadkar's position, they see alignment encompassing only the areas covered by the Good Friday Agreement. They believe this can be achieved by way of a deep 'Canada-plus' free trade agreement, with services bolted on. It is hard to see how Theresa May has the political capital to resist them.
What has not been fully appreciated to date is that the position of the Brexiteers is not a million miles away from that of the EU's chief negotiator. Michel Barnier has been unambiguous that if the UK sticks to its intention to leave the single market and customs union, the best it can hope for in its future relationship with the EU is also a Canada-like arrangement, but without services.
When the UK and EU talk about services, they really mean financial services, in which the UK has a huge trade surplus with the EU, given the position of the City of London as Europe's financial capital.
So when the dust settles, the sticking point in discussions on the future relationship will be whether the UK financial services industry will continue to enjoy unimpeded access to the EU. That is a battle the UK is almost certain to lose, given the opportunity it offers the EU financial industry.
Ultimately though, both sides are likely to accept the reality that within the constraints they face, a Canada-style deal represents the most achievable relationship they can aspire to.
As this realpolitik gains momentum and our influence wanes, we face the risk of being squeezed in the pressure for a deal. A Canada-like relationship between the UK and EU would fall well short of the Taoiseach's bottom line that Northern Ireland will maintain full alignment with us - and the assurance that there won't be a hard border on the island of Ireland.
While his options are limited, it may well be time for Varadkar to get his EU colleagues to come clean on their preferred future relationship with the UK. He may not like their answer.
