being taken to protect the city. >> this is where everybody has to be on their toes. i know complacency can set in at times but certainly not at an event like this. >> reporter: in the wake of the isis-inspired attacks in nice. most being used as a protective barrier around the perimeter of times square to ward off a truck-style attack. >> we live in a changing world now. it can't just be about what happens in new york. >> reporter: the nypd is in constant communication with foreign departments gaining intelligence and sharing police strategy with cities abroad. in london, there is added security at the changing of the guards. heavily armed police were unavoidable in berlin as they stood posts behind concrete barriers at a christmas concert. christmas markets were heavily patrolled and in france, a boost of 10,000 soldiers on the parisian streets over the holiday period, adding to the officers working around the clock.