The fate of the state and local tax deduction, or SALT, is dividing lawmakers by geography as well as politics.

Class conflict has erupted in Trump’s America – within his own Republican Party. The party controls both houses of Congress, as well as the presidency. But their struggle to agree upon tax legislation shows that Republicans in Washington are challenged by the clashing interests of their traditional wealthy constituents and their new working-class base.

There are as many factions among Republicans in the upper chamber as in the House. Both chambers have to agree on the final product. It won’t be easy.