$2 trillion is parked overseas. It is parked overseas because the opportunity cost of bringing it back here is higher than leaving it overseas, mostly due to corporate tax rates that are higher than they are overseas. We can leave tax rates as they are and gain $0, we can lower corporate tax rates and hopefully bring a (large) fraction of that back here to benefit the economy as a whole, or some other solution that increases the wealth of the nation that has not been thought of yet.

If you're considering an alternate solution, bear in mind that history has shown that imposing taxes in situations like this results in increased friction in moving the wealth back and generally less wealth for the nation imposing the taxes.

So maybe it bears some resemblance to trickle-down economics, but is there even a marginally better solution available?