Next month, the Irish and British people should be celebrating the 20th anniversary of the Good Friday Agreement. The agreement serves as the cornerstone of the power-sharing deal between Northern Ireland’s unionists and nationalists that helped bring an end to years of violence. It has cemented a long-term constitutional settlement between the United Kingdom and Ireland, in which both states agree that the people of Northern Ireland are free to choose their own destiny. There won’t be any Happy Birthday party this year, however. The power-sharing arrangement that governs the North is on hold, and some prominent British