Sombre mood on the campaign trail after an unthinkable tragedy
In public, the tone was appropriately muted and restrained after the very tragic turn of events in the Brexit referendum.
Privately, however, Enda did not hold back - warning his Northern Irish, Scottish and Welsh counterparts of the perilous risks they were facing if Britain decides to go down the unlit road of leaving the European Union.
"You really went for it in there," a startled Northern Ireland First Minister Arlene Foster told him afterwards.
But heads had nodded around the table, sources at the private meeting said. Apparently, most of the leaders present at the British-Irish Council summit in Glasgow at least acknowledged his concerns on how this could go.
Not Secretary of State for Northern Ireland, Theresa Villiers, however. Resolutely in the Leave camp, she later scoffed at the very real fears that the border might have to be reimposed.
After the devastating events of the previous day, the politicians were in a sombre, reflective mood and in a difficult position - unable to speak freely and yet without even the heart to do so, the loss of MP Jo Cox weighing heavily on their minds.
They held a minute's silence for her amid the privacy of their meeting, afterwards paying tribute to the Yorkshire public representative, who paid the ultimate price for her humanitarian passion and political beliefs.
With both campaigns suspended - with word coming yesterday that the Leave campaign will not take up again until Monday - the political clock had stopped.
This could well prove to be the turning point. At any rate, it has entirely changed the tone of the campaign - which had spiralled out of control in ugly, ill-tempered fashion with the flotilla stand-off on the Thames, with Bob Geldof giving the fingers to the Leave side - along with handing them the high moral ground.
That day, Jo Cox had, too, been out on the Thames - the last devastating photo showing her hair flying in the breeze along with her defiantly fluttering 'In' flag, her two tiny children and husband in tow.
With the unveiling of Ukip's inflammatory posters showing a stream of desperate-eyed migrants flocking into Slovenia under the headline 'Breaking Point', the Leave side are now scrambling.
Jo's husband Brendan tweeted a brief "Vile" in response to the poster.
Commentators, already sickened by the extremist bent of the debate and horrified by the loss of such a shining political light are asking how British society had got to this point.
With the referendum taking place next week, the pendulum is now swinging furiously once again amid crushing grief, when 24 hours ago, the result seemed a triumphant 'Leave'.
Whatever happens now, there can be no place for triumph or euphoria.
At the summit, David Mundell, Secretary of State for Scotland, pleaded for a "push back on the vilification of the political class" with some of those present saying they had been subject to abuse and threats. "Recently, abuse and name-calling of politicians is just a matter of course," said Mundell.
"When people hear about Jo, they realise she's the exact opposite," he said, mentioning the huge personal sacrifices she had made with her young family in having to come to London "because she wanted to do better for her own community and the wider world".
"That is not the stereotype of politicians that we hear too much about, I think," he said.
But the politicians seemed to think it unworkable when they were asked if their security needed to be increased or that the public's access to them should be restricted.
Martin McGuinness said he refuses to be forced to change his routine by people who had threatened him in a bid to scupper the peace process.
Enda said access to politicians is a key component of the political system on these islands. Once again, he "unashamedly" called on the Irish community living in Britain to vote Remain, saying it was not his place to lecture but that he felt it important to address them on this issue.
And in a veiled reminder to attendees of the Summit, he warned that in the event of a vote to Leave, there will be no one to speak for Scotland, Wales or Northern Ireland at European Council meetings, which will lead to a "massive change" in the situation.
He was almost alone in the leaders in not coming out to give interviews afterwards, as he headed off to a British Irish business network event - still campaigning. Quietly but with no less urgency.