It’s not official yet, but it seems certain: The Republican Party is a house divided against itself. In its early days, Abraham Lincoln recalled the words of Mark’s Gospel and warned that the nation divided could not stand. These days, the warning is true of Lincoln’s party.

The Republican Party could go the way of the Labour party in the United Kingdom in 1979: After choosing radicals to lead them, party members cheerfully turned their backs on their moderate colleagues.

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