How do countries other than the United States deal with their national security?
Since your questions have been about terrorism and police powers and such, I assume that you are talking about national security in that sense, not in the sense of protection from actual military threats from other countries. My answer is based on this assumption.
Different countries of the world deal with their national security in very different ways. The democracies of the world are generally much less repressive than countries that do not have democracies. The United Kingdom, for example, has the Terrorism Act of 2006 that is regarded as somewhat strict for a democracy. It criminalizes statements that would tend to make their audiences think that terrorism is good and that terrorist acts are things that they should emulate. Although this seems expansive, compare it to the ways in which China deals with national security. China has the ability to censor the internet and has used this power to do such things as banning the use of the word "jasmine" for fear that people would use social media to start a "Jasmine Revolution" in China that would be similar to those of the "Arab Spring."
So, there is no one way that other countries deal with national security issues.