Given that more spams originate from certain countries than others, I wonder what would happen if total bandwidth capacity of each country is choked by percentage of spam in outgoing e-mail.  For example, if Korea's bandwidth capacity is X and 70% of e-mail originating from Korea is spam, then Korea's bandwidth is limited to 30% of X.

My guess is that choking at the national level will encourage each country to choke at the network level which will subsequently encourage ISPs and broadband operators to choke at the connection level.  This will encourage spammers to use zombies at other countries which will in turn encourage that country to crackdown on spams.

Hopefully, spammers will eventually run out of places to spam from.