[jdubs]

Blocking ips from countries is not an exact science as network blocks are traded frequently and networks do not conform to lines on maps.

[dredmorbius]

My read was that the software was blocking specific CIDR blocks, and those blocks were within the allocations of the listed countries.

Not that he was doing country-wide blocks. Though I could see doing that in some cases (e.g., you do no legitimate business with country Z, but get some high percentage of attack traffic from it). Metcalfe's law fails to account for the fact that many nodes in fact contribute negative value to the network.

I prefer CIDR-level blocks myself, if single-IP blocks prove too whack-a-mole-ish.