

Trump was in real estate. He wants land. Greenland does have leverage. They could refuse the US offer. Greenland doesn’t have the power to stop a US invasion but such an invasion would be illegal. Consequently, a subsequent administration could withdraw. However, if Greenland signs a deal, that would be legally binding.
Republicans and Democrats might not be interested in eliminating gerrymandering. That’s the reason neither party has ever proposed having a computer program draw districts.