Pete, that was a British negotiating trap from the outset. Deny all responsibility for a border that Britain militarily enforced from 1921 until the Good Friday Agreement.
London gladly negotiated a ceasefire and a settlement. That settlement granted Irish people freedom of movement, freedom of nationality and freedom to determine our own constitutional future.
That same international treaty, that was hard earned by Westminster, has now scuppered Britain’s storybook Brexit because they are being forced to respect the legal agreements that they sought to introduce.
Blame London, not Brussels.