Muhammad divided the world in two sectors. One he called Dar us Salam (House of Peace) and the other, Dar al Harb (House of War). All countries, where Islam is not the ruling authority, are Dar al Harb. It is the duty of the Muslims to wage Jihad in Dar al Harb, overthrow the governments and force people into submission. This is the only kind of peace that Islam recognizes.
The only rule Muslims know is to win. It does not matter how. All rules can be broken as long as they win the war. They can lie, they can deceive, they can break their treaties as Muhammad did, they can ambush or use terror, assassinate, massacre the children and bomb civilians. Muslims can even kill each other as long as this improves their chance of winning.
Islamic terrorism is not common crime but an act of war. Jihad is war. For the Jihadi it is a war; we must also accept it as such. Home grown Muslim militants must be treated, not just as enemy combatants but as traitors.