‘A son of Ireland’: how Biden’s Irish roots shape his political identity

US president's heritage is a form of soft power as he travels to Belfast and Republic of Ireland to mark Good Friday agreement

It was a line guaranteed to raise a smile. As we know, every American president is a little bit Irish on St Patrick's Day," Leo Varadkar, the Irish taoiseach, observed during last month's celebration at the White House. But some are more Irish than others."

Joe Biden is as Irish as it gets. On Tuesday he travels to Belfast, Northern Ireland, to celebrate the 25th anniversary of the peace accord that helped end decades of deadly sectarian violence, then on to the Republic of Ireland for stops including Dublin, County Louth and County Mayo for what will feel almost like a homecoming.