St. Patrick's Day Celebrations Unite US Presidents and Irish Leaders.

The tradition of presenting a bowl of shamrock to the US president on St Patrick's Day began in 1952 when the Irish Ambassador to the US delivered a box of shamrock to President Harry Truman. The gesture was seen as an attempt to warm the relationship between the two countries, which had soured over Ireland's neutrality in World War Two. The tradition has continued ever since, giving the Republic of Ireland enviable access to the US president every March.