There is no regulation on USA air transport except the terms on air safety, so there are countless numbers of airlines in USA, and there are lots of very short distance routes of less then 300 miles, and of very high frequency. This causes serious congestion of airports on USA north eastern coast.
But most other countries have regulation on air transport on routing. For expamle, the China government bans the operation of any air routes shorter than 500km (320 miles). This saves airlines resources, makes the airports less congested & makes better use of highways & high speed rails.
So a question rises: Should USA enforce some regulations on air service routing, to ban the operation of very short distance routes?
I think this is necessary, with operation of routes shorter than 200 miles banned (unless there is no highways or high speed railways connecting the 2 cities), as this greatly reduces the congestion of the airports.
Some people may say this would cause serious inconvenience to passengers. But actually it takes as much time to take very short distance air routes as travelling on highways or high speed railways, because it takes time to travel between city centre and airport, while highways & high speed rails can reach city centre directly.
Welcome for discussion.