"Fuck the poor"

These are conservatives we're talking about. That's the beginning and end of their logic.

The figleaf is the usual trickle down "tax cuts will boost the economy, rising tide all boats, yada yada" nonsense that has been resoundingly discredited for decades. It doesn't matter. The tories don't care because they know they're just doing this to make rich people richer at the expense of poor people, and their voters don't care because they'll believe anything if it means fucking over immigrants.