They have got close a few times (reaching the finals five times in 19 years, losing in game 7 four times, ouch).
The teams are not distributed to have a more consistent fans-per-team ratio everywhere (Canada has lower population, but much much higher hockey interest, so fans-per-team is higher in Canada). Adding 2-4 teams would probably bring the fans-per-team ratio closer to USA numbers.
They have got close a few times (reaching the finals five times in 19 years, losing in game 7 four times, ouch).
The teams are not distributed to have a more consistent fans-per-team ratio everywhere (Canada has lower population, but much much higher hockey interest, so fans-per-team is higher in Canada). Adding 2-4 teams would probably bring the fans-per-team ratio closer to USA numbers.