Would someone be generous enough to give me a quick rundown of a) the pros and cons of the US/Mexico/+ defecting to CONMEBOL permanently, and b) the odds of it happening?
Pros
- Higher quality, more interesting competition for club and country
- Regular participation in Copa America >>>>>>>>> regular participation in the Gold Cup
Cons
- Legitimate chance of not qualifying for any given World Cup
- Hellacious travel. Seattle-Buenos Aires is 1,000 miles farther than London-Tokyo. Even the best-possible-case travel scenario of Miami-Caracas is comparable to London-Saint Petersburg. Even regionalization of tournaments can't fully save you here.
Chance of it happening
Minimal. USA and Mexico have a cushy situation in CONCACAF. Mexico has it especially cushy, since they send club teams to Copa Libertadores. For all of the appeal, do the US and Mexico really want to give up a 95-98% chance of qualifying for the World Cup every time?
I'm not sure which bodies would need to approve such a move, but I would expect this would be very hard to pull off in the environment of FIFA politics. The loss of USA and Mexico would leave the Caribbean high and dry. But who cares about the Caribbean? FIFA does - the federations in the Caribbean Football Union have 3x as many votes as the US, Canada, Mexico, and Central America combined. The CONCACAF gravy train that flows from the money generated in the US and Mexico would end and that would be unacceptable to the Caribbean, who probably have enough sway in FIFA to block such a move.
The Central American countries probably wouldn't be happy about it either, unless they were taken too. And while CONMEBOL may well be interested in the prodigious soccer dollars of Mexico and the US, they'd have little interest in the likes of Honduras and Costa Rica, to say nothing of the rest of UNCAF.
So basically, don't hold your breath.