The seeds planted by then taoiseach Sean Lemass and US president John F Kennedy in 1963 have yielded a rich harvest over the years. More than a quarter of a million people employed directly and indirectly by US companies in Ireland is just one aspect of it. The successful conclusion of the Belfast agreement following a negotiation process chaired by US senator George Mitchell is another.
But those outcomes would not have been possible without the continuing efforts of statesmen, businesspeople and ordinary citizens in the two countries over the past 50 years. "Lemass took the message that Ireland was open for business across the Atlantic," says American Chamber chief executive Mark Redmond. "He appeared on the cover of Time magazine and he sowed the seeds of the annual presentation of the shamrock and the Speaker's Lunch on Capitol Hill. That's a very important date and it has now been confirmed by president-elect Trump.
“The Irish have had an extraordinary impact on the USA,” he adds. “Every corporate leader will call out the extraordinary contribution of the Irish to the success of organisations around the world. We now have Irish people in senior leadership positions in the US and that all goes back to Kennedy and Lemass.”
One of the earliest of those Irish leaders of a US corporation was Tony O'Reilly, now Sir Anthony O'Reilly. When Lemass was visiting Kennedy in the White House in October 1963, the young O'Reilly was working on the creation of the Kerrygold brand to spearhead exports of Irish dairy products. Six years later, he joined Heinz and eventually rose to become its global chief executive in 1979.
Among his greatest contributions to the Irish-American relationship was his creation, with his friend Dan Rooney, of the American Ireland Fund in 1976. The fund has raised more than $500 million to date to fund charitable causes, many of them focused on peace building on the island of Ireland.
Rooney made a significant contribution to the relationship in his own right and this was recognised in July 2009 when he was appointed US ambassador to Ireland by President Barack Obama.
The Kennedy family’s commitment to Ireland has been unwavering over the years but they were by no means this country’s only friends on “the hill”. President Kennedy’s youngest brother Edward formed a formidable alliance with fellow Irish-American politicians Thomas P “Tip” O’Neill, Patrick Moynihan and Hugh Carey to become what was dubbed the Four Horsemen.
Their work led directly in 1977 to President Jimmy Carter becoming the first US president to make a direct statement on Northern Ireland. That began a sustained period of US involvement in Northern Ireland which was carried on by presidents Reagan and Clinton and had its culmination in the signing of the Belfast agreement in 1998.
More recently, Irish business leaders such as Dr Michael Smurfit, Denis O'Brien and Don Godson have left their indelible imprints on the transatlantic economic relationship and contributed to a situation where Irish companies now employ as many people in America as do US companies in Ireland.