These days, it seems like countries don't invade each other like they used to. It just seems like they'd rather do small, covert raids or just outright overthrow a hostile government.

Countries do still invade one another. Ethiopia invaded Somalia in 2006. Israel invaded Lebanon that same year. America invaded Iraq because... well, just because. But the world's most recent invasions weren't really conducted with the idea of actually annexing territory.

The U.S. and South Korean governments might want to just keep the North at bay instead of overrunning the government completely. A 2013 RAND Corporation research paper estimated the cost of unification to be upwards of $2 trillion dollars. This is not only to pay for the

This is not only to pay for the war but for food for the population and the restoration of all the infrastructure the Kim regime neglected over the past sixty-plus years. Gen. Marks believes the North and South will continue to only use short, contained attacks on each other, making a full-scale war unlikely.