The department of industry is the department that takes charge of all the affairs related to industry, whether they pertain to heavy industry like manufacturing of motors, engines, vehicles, materials, electrical equipment, or light industry. All factories public or private property, which have a relationship with the military industries, must be based on the war policy. This is because Jihad and fighting require an army, which requires weapons. In order that these weapons be of the highest level and fully available, it is necessary to have an industry within the State, particularly the military industry due to its strong relationship with jihad. .

In order that the State becomes independent of other countries and does not become influenced by any of them, it should manufacture and develop its own weapons by itself. This makes it independent and in continuous possession of the most advanced and strongest weaponry, regardless of the level of development and advancement of weapons. It would also have at its disposal, all that it needs of weapons to intimidate, both the evident and potential enemies, as Allah (S.W.T) says:.

“Make ready for them all you can of (armed) force and of horses tethered, that thereby you may dismay the enemy of Allah and your enemy, and others beside them whom you know not. Allah knows them.” [TMQ 8:60] .

As such the State would have its own will, produce the weapons that it needs and develop them continuously so that it owns the strongest and most developed weapons in order to terrify all the evident and potential enemies. Therefore it is a duty upon the State to manufacture weapons by itself and it is not allowed to depend upon other States, because this allows other States to control it, its will, its weapons and its fighting..

It is quite clear in the world today that the States which sell weapons to other States do not usually sell every weapon, particularly the most developed weapons. They do not even sell weapons except with certain conditions that cover their utilisation. They will not sell them except in quantities that they, rather than the purchasing countries, decide. This gives the State which sells arms, authority and influence over the State which buys the arms enabling it to enforce its own will upon the purchasing State, particularly if it was involved in a war. In that case it would need more arms, spare parts, and ammunition, which would increase its dependence on the State which exports its arms and increases its submission to other states demands. This allows the State which exports arms to control it and its will, especially in times of war and in times of great need for arms and spare parts. Hence such a State would make itself, its will and its entity hostage to the State that exports arms to it. Therefore, for all these reasons, the State has to independently manufacture its own arms and everything it requires for its war machine and spare parts. This can’t be achieved unless the State possesses heavy industry and started to build factories which produce heavy industry, both military and non-military alike. Thus it is necessary that the State has factories for producing all types of atomic weapons, rockets, satellites, aeroplanes, tanks, spaceships, mortars, naval ships, armoured vehicles, and all types of heavy and light weapons. It is necessary that it has factories which produce machines, motors, materials, electronics and factories which have a relation with public property and light factories which have relation with the military or war industries. All this is required by the duty of preparation which is obliged upon the Muslims by the saying of Allah (S.W.T): .

“Make ready for them all that you can of (armed) force.” [TMQ 8:60] .

Since the Islamic State conveys the message of Islam by da’wah and Jihad, it should be a State which should be continually ready to carry out Jihad. This requires the existence of heavy and light industry built upon the basis of its war policy. Thus in case it wanted at any time to transform these factories for military purposes, it would easily do so at any time. Therefore all the industry in the Khilafah State should be based on the war policy, and all the factories, which produce the light and heavy industries, should be based on this policy, so that it becomes easy to transform their production to military production at any time the State requires.