In regards to territoriality and taxation, this is not limited in scope, yet central to the tax reform plan.

U.S. companies are currently incentivized to move their headquarters and jobs overseas (you must have heard of "inversions").  Once overseas the incentives are against hiring Americans and for hiring non Americans.   More of this will happen without change.

A key thrust of the tax reform is to remove the laws that disadvantage American firms and Americans, and to bring more money, business, investment and jobs into America while increasing the competitiveness of American firms and thus exports.

And of course along the way a thrust is a vast simplification of the tax rules.

I would like to highlight that  - territoriality - should not all be about companies, this must be for INDIVIDUALS as well, so that the U.S. ends its unjust and un-American claim of tax jurisdiction over residents of other countries and double taxation of U.S. persons living overseas.