1) money will come back into the US and help our economy
It's unproven that money being shifted from an overseas bank to a US bank will "help the economy".
In fact, if it comes back and ends up in the hands of a few or used for one company to buy another it could very well hurt our economy.
Further, it's not "the economy" that needs help. It's people. And for the past 35 years, there's been little proof that helping the former necessarily helps the latter.