Armed police officers and sniffer dogs at each airport entrance please, at least it will help a bit as a deterrant. Airports are nevralgic centres for entire countries. What happened in BRU is extremely easy to repeat, we have to learn to live as they do in Israel and be more pro active and extremely vigilant.
The problem with this type of reaction is that 'they' have then won.
No one would ever accept this type of security at a railway station yet they too are targets so why should aviation be treated any differently.
The objective surely is not to just prevent attacks but to permanently 'eradicate' the individuals responsible.