Earlier quoted context omitted.
Again, its easier to buy a cheap VPS in a country that is at odds with the one you're in. Then, any intelligence the other country gets will likely not be sent to the country of residence. Ally countries usually have extradition treaties, and have a greater chance of sharing intel.
Correlation is still quite easy in that scenario, unless you're sharing that VPS with a thousand other people. NSA has your international traffic logged and timestamped. If you're doing nefarious activity from a non-MLAT country's IP, and you're the only one connecting to it from the US, it's a simple matter of parallel construction for domestic law enforcement to pop you.
Couldn't that be countered by using two foreign IPs for your VPN, one for your inbound connection and another for your outbound traffic? It would make it more difficult to correlate your US IP with the outbound VPN traffic without extra information.