Why is that a problem? Hiding has always been easier than detecting in the real world. People are too used to computers which make detection easy. But before c

Why is that a problem? Hiding has always been easier than detecting in the real world. People are too used to computers which make detection easy. But before computers, a king would have to physically send tax collectors to gather money and soldiers to guard the borders. Being able to spot all enemies sneaking in was never practical, and still isn’t. The US government wishes it was that effective.