It will be hard to challenge an agreement rich in rhetoric but sparse in substance.
So far, so predictable. A collision between one country and the 27 other EU member states was bound to favour the latter. A collision between reality and the utopian fantasies of the Brexiters was bound to favour the former. And a collision between the grubby embrace of the Democratic Unionist party by the Conservatives and the demands of the Irish government was bound to occur sooner or later.
And so the UK — once famed for wily statecraft — has blundered into a volley of self-inflicted Brexit concessions and is reduced to begging Arlene Foster, the DUP leader, for permission to proceed.