Too late. There are only 7 billion people. If you don't think every major intelligence service (and a few large companies) has built a database of every person'

Too late. There are only 7 billion people. If you don't think every major intelligence service (and a few large companies) has built a database of every person's vital statistics you are naive. If I was the US government I would be in the process of building a full world family tree using DNA collected from battlefields and attacks. I would want to know when an attacker's cousin is entering a certain country.