LyrArc Article Gist
Greg Ip of the WSJ provides this exceptional report offering readers remarkable clarity on what the Republican Tax Law does- its high and low points. 

High Points

1. It reduces the corporate tax rate to bring it in line with other advanced industrialized countries. The corporate tax rate in Germany and Japan is 30%, in the UK it is 19%. For 5 years businesses can write off capital equipment immediately instead of depreciating over a couple of years. This could boost investment and growth.

2.  The law takes aim at deductions that led to distortions. It limits the mortgage interest deduction, and caps the deduction for state and local taxes. This removes the incentive to pay more for homes that exacerbated the housing crisis in 2008. The Alternative Minimum Tax is largely removed.

The Low Points

1. The biggest drawback is that lawmakers did not properly fund the tax cuts. Of the 10 costliest tax breaks nine were not touched, including employer health insurance, retirement savings, capital gains. Only the state and local taxes deduction was reduced. And a new tax deduction  was created, a 20% tax deduction for small business (proprietors and partnerships) paying taxes on their individual tax returns. Taxes on the wealthy or value added taxes, reducing tax breaks, is how other advanced industrialized countries paid for the corporate tax cuts, but did not happen here.

Additional economic growth  to generate added tax revenues is the way Republicans in Congress say this is funded. Yet this is a questionable assumption as Britain reduced the corporate tax rate to 19% without seeing a surge in economic growth, as Greg Ip pointed out in an earlier WSJ article. At best the Joint Committee on Taxation estimates $500 billion over a decade in added revenues from added growth leaving $1 trillion to be added to the deficit. The WhartonPenn Budget Model (WPBM) estimates only $140 to $367 bill from the additional economic growth resulting in added tax revenues. Under this model only 0.03 to 0.08 percent added U.S. economic growth per year is expected from the Republican Tax Cuts. Such a situation would be bad  for the U.S. as the gradual improvement in Debt to GDP ratio to 78% following the financial crisis of 2008 would be sharply reversed taking the ratio to 97% by 2027. An unsustainable trajectory which will require tax increases in a few years and hurt investment in education, health and infrastructure into the future. This is what worries many experts most on both sides of the political spectrum today about what the Republican Congress has pushed through for a legislative "victory."

This is why experts believe this is not serious tax reform and will require a new effort after 2019.