Little at the moment.  A largely open border to the rest of the Eurasian continent allows for an inflow of weapons even if you successfully collected all that are already here.  Weak explosive devices can be made with common(ish) materials.  Even with tight controls you will still get knife attacks.  Just look at Palestine recently.<p>Tight controls will require a more authoritarian government.  I for one don&#x27;t want that but I expect we will get it and the masses will demand it.  Yay for neighbours.