He was accompanied by his partner, Dr Mathew Barrett, who had been invited with the Taoiseach to return to the residence of US vice president Mike Pence in Washington DC for an early breakfast.

Mr Pence has been a vocal critic of gay marriage, and once said in a previous speech that it would lead to “societal collapse”.

And there was tension in the air as the Irish delegation arrived at the US Naval Observatory just after dawn in Washington.

The vice president tried to break the ice, telling Matt that Chicago (where the Taoiseach travels to today) was a great city (Mr Barrett also worked in The Windy City for several years).

But the morning sun was only up and Mr Varadkar had other thoughts he wanted to discuss.

During the traditional breakfast, pleasantries were exchanged. Mr Pence recalled working in Tubbercurry, Sligo, in a “rainy” Ireland. And amid fraught Brexit negotiations, there were assurances of solidarity.

“The US stands with the Republic as the UK continues to work through the issues with Brexit. I look forward to when we can begin talks about expanding trade,” said Pence.

Then it was the Taoiseach’s turn. His partner Matt looked on as Leo Varadkar took to his feet to address the congressmen and Irish-American figures in front of the media.

He too spoke of bonds between the US and Ireland, but also of a country that has changed.

Describing growing up in Ireland, told the breakfast guests: “I knew at the time that I lived in a country where if I tried to be myself at the time, it would have ended up breaking laws, but today that has all changed.

“I stand here, leader of my country, flawed and human, but judged by my political actions and not by my sexual orientation, my skin tone, gender or religious beliefs.”

It was a stunning message and one delivered in the frame of St Patrick’s Day and Ireland’s recognition around the globe.

Ultimately, Mr Varadkar told the conservative vice president that he would be travelling to a changed, modern Ireland where freedom of expression, equality and open sexuality were respected.

Then it was off to meet the real boss, US President Donald Trump, at the White House.

The traditional St Patrick’s Day meeting in the Oval Office can be a mixed affair, depending on the incumbent in Washington as well as the issues of the day.

There was no lack of the latter when the media scrum scrambled into the Oval Office to quiz the two leaders. And The Donald was in a talkative mood.

While Leo Varadkar had crossed the Atlantic in the hope of maybe talking about the Good Friday Agreement, peace in the North and the undocumented Irish in the US, there was one subject he just couldn’t get away from: Brexit.

And with that came a flood of comments from Donald Trump about trade, tariffs, and messy negotiations with the EU that ultimately drove a coach and four through any sense of solidarity.

This meeting might have been to mark St Patrick’s Day, with some green and even orange in the room, but suddenly Leo Varadkar had to take a lecture on Brexit and EU trade.

Mr Trump said Brexit was “tearing” Britain apart. “It’s a shame it has to be that way,” he quipped.

“I’m surprised how bad it has all gone from a standpoint of the negotiations.”

And he saved his harshest words for the EU. While the US was open to a new trade deal with Britain, the EU faced sharp economic sanctions if it refused to play ball with the US on trade.

As Leo Varadkar sat silently, the US president laid down a gauntlet.

The US would do “something that is pretty severe economically, we are going to tariff a lot of their products” warned Mr Trump.

This wasn’t exactly the message of solidarity Mr Varadkar had been seeking. And even his best attempts to highlight the peace process barely caught Mr Trump’s interests.

And questions about trade, Brexit, the planned wall with Mexico, and US immigration policies kept coming. Suddenly, Leo Varadkar was drowning in his own St Patrick’s Day green nightmare.

As such, the day was best rescued during the traditional shamrock bowl presentation back in the White House last night, after the fast-paced day geared down a bit.

Surrounded and comforted by Irish-Americans, the Taoiseach was able to emphasise the importance of the peace process.