If you want to make an argument about what a port is, picking land "points of entry" isn't a good argument. Airports are a better yardstick. A new Capitol Sta

If you want to make an argument about what a port is, picking land "points of entry" isn't a good argument. Airports are a better yardstick. A new Capitol State could easily establish both a port and points of entry if it so chose, the Potomac is somewhat in practice (and legally) a navigable river and there are US highways and interstates that go thru Washington DC. Furthermore the WMAA would likely come under the control of the city.