The Taoiseach, Enda Kenny, will find both the queen and the British prime minister, David Cameron, in pretty buoyant form when he meets them this week.
The queen is elated not only because of the public relations triumph of the William and Kate wedding, but also because, for the first time in 30 years, she has a horse good enough to run in the Derby.
Her last runner, back in 1981, could only finish fifth but this year's hopeful, Carlton House, is the hot favourite to win the race.
Mr Cameron is feeling cheerful because, after some difficult months, he believes he has got his coalition government back on course. The Conservatives are rising in the opinion polls and Labour's leader, Ed Miliband, is the constant target of internal sniping from among his own ranks.
Mr Cameron has been taunted for years about his upper-class schooling at Eton and Oxford and his equally upper-class ancestry -- he is a distant cousin of the queen.
His stock riposte to such comments is that what counts is not where you came from, but where you are going.
That will be very much the theme for any public statements that he and the queen make this week. Leaving aside the unknown unknowns of the security risk, they are both acutely aware of the political and diplomatic sensitivities of the event.
It is 18 years since the idea of a state visit by the queen was first put forward and it is easy to see why, on both sides of the Irish Sea, the time never seemed quite right.
Now, on top of all the historical baggage from the past, there is the equally fraught matter of the financial relationship between Britain and Ireland. The Taoiseach said yesterday on BBC television that he would again be thanking the prime minister for the bilateral loan which the treasury extended last year, but it is a notorious truism that lending money to people can be a quick way of undermining relations with them.
Mr Cameron, in reality, is in no position to play the heavy-handed bank manager in Dublin. The financial position of Britain is not very much healthier than Ireland's. In fact, the main factor in Britain's favour is that it has so far managed to hold the confidence of the financial markets and, even more crucially, it has the Bank of England available, when necessary, to create spending power.
There are also people in the government, such as the universities minister, David Willetts, who vividly remember the traumas of Britain's close encounter with national bankruptcy nearly 40 years ago.
Mr Willetts remarked last week that it is very complacent to claim there is no risk of a eurozone-style crisis in Britain: "I entered a shell-shocked Treasury as a junior official in 1978 just two years after we had become the first advanced economy to have to go to the IMF for a bailout. That humiliating deal was signed in the very same grand treasury room on whose Whitehall balcony Churchill had stood to wave to cheering crowds on VE day. I always thought those twin events, 30 years apart, captured the story of our post-war decline."
Churchill would have been delighted at the queen's visit. Back in the 1950s, when the government was almost as short of cash as it is today, he ordered the treasury to keep on providing the Curragh with the prize money for the Royal Whip race each year as a goodwill gesture.
There has never been any prospect that his long-held hope of getting Ireland back into some form of Commonwealth relationship with the UK would be fulfilled. But the emergence in Scotland of a majority government committed to achieving independence may give an intriguing insight into how different the history of Ireland over the past 100 years could have been.
The Scottish first minister, Alex Salmond, is a royal groupie. He has pledged to keep the monarchy if the Scots vote for independence and, unlike both Tony Blair and Gordon Brown, he was invited to the royal wedding last month.
Blair is one of three former prime ministers whose Irish ancestry is highlighted by the UK Foreign Office in its website's comments on the royal visit. The others are John Major and the late James Callaghan.
Foreign office diplomats will be keeping an eye on the drink they are given at the official receptions in Ireland this week. They have been told by the treasury to cut costs and they are planning to sell off some of the 40,000 bottles of vintage wine that they have in their cellars in order to cut those costs.
When US President Barack Obama arrives in London next week after his visit to Ireland, he will not be offered champagne but British sparkling white wine.