Before we went to the United States last year several people warned us about heavy-handed security, especially at the border.
We were photographed and finger printed at the immigration control but the people doing it were courteous and efficient.
However, once in New York we found ourselves going through security checks and x-rays at most tourist attractions – sometimes multiple checks at various stages of a tour of the same place.
This is the USA’s reaction to the 2001 terrorist attacks.
But the shooting of 12 people at a theatre in Aurora, Colorado shows the danger isn’t just from without and raises the question of what can a country do about the enemy within?