It's the easiest plan to sell
The relationship between politicians and business is always a tight one, especially in the US.
Anytime a politician can turn to his business chums or lobbyists and offer them a tax cut is one sure fire way to get support and the Champagne corks popping between them.
To a lesser extent, the same applies to individual tax payers, that is until the ones that have to pay for those tax cuts get the revised bill.
Should it be that way? No but it is what it is. Expect more corks to pop when US stocks open shortly.
US politics: You scratch my back..
The only thing I'm worried about now is whether these big promises are going to be let down by the detailed reality. The market now has an idea on what's coming so that might make the upside harder work now. Unless we get something we don't know later, we could see this positivity buying subject to profit taking after the official announcement.