What makes you believe this form of tax reform will tickle down to the middle and lower income citizen?
Because it can't do anything else in a free market system.
First of all, the majority of the cuts are directly going to the middle class. But all money returned to the taxpayer will ultimately have one of three outcomes. 1) It is spent, where it "trickles down" in the form of job opportunities, salaries, tips and wages. 2) It is invested, where it "trickles down" in the form of credit and loans made available at reasonable interest rates for those who need capital. Or invested in stocks where it "trickles down" into a lower income person's retirement account. And 3) Kind of nonsensical, but the money can be buried or burned in a fire.... this effectively increases the value of remaining money.
This is how a free market capitalist system operates. Everything trickles down.
Simple explanations are for simple people, thanks for you comment Simon.
1a. The increase in money in the hands of the investor class can be invested in the States, but more and more of the money in the hands of the very wealthy is invested overseas, which does not benefit those promised it will trickle down to anyone who have been promised by Trump and Ryan, et al, that it will.
2a. There is no mandate to raise the hourly wage minimum, or the salaries of working Americans in the bill; there is no mandate for money repatriated from earnings out of the country to be used within our country to do anything. They can simply give more to the Executive Management to spend on vacations in Europe and benefit their economies.
3a. That's silly. The greatest risk to such valuables is created by the greed of the power elite, their lust for power and money. It festers what the right wing greatly fears, a mass movement to violently take their wealth, some thing people educated in history and political science understand.