Why does American Soccer (football) not have a promotion system?

Question

I would love to see my Portland Timbers be promoted up to the MLS. But why does the MLS not practice this system seen all over Europe and the world over?

Answer 1

because americans don't like soccer enough to support losing teams. Minor league baseball does not go up. only the players promote. if portland had a tram in mls the gate for the away games would be poor! enough said!

Answer 2

I think American clubs buy their way into a league after petitioning for acceptance. I'm not sure how a team would like being relegated after they just bought into a league.