to sit and negotiate with the so-called extremists no matter if they were Muslims or what. Study from correct sources about thier religion, culture, principles, minds and discuss with them what they need and what they are expected to follow and respect.

This is the only way to avoid terrorist actions and not by attacking them or banning thier religion. As others said banning minarets or even mosques won't erase extemism, but will make it much worse.

Governments must know that many of those extremists are citizens and not only immigrants or passport holders.