>Either that, or it's the defining moment of his presidency- if it all goes well. Which it might, according to ecomomists.

It very well might go well.

Not because of any of its provisions (they seem to change day to day) but because we are definitely in a rising economy.
One of my clients' business closely follows the consumer market and his business is growing like gangbusters.
The job market is almost at the best levels of the much heralded Clinton boom, and it will almost certainly surpass it.
If that happens incomes and tax revenues will skyrocket and Trump, being Trump, will claim it all happened because of the tax bill.