Ruses of war and the employment of methods necessary for obtaining information about the enemy and the country are lawful.

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Examples of lawful ruses: surprises; ambushes; feigning attacks or retreats; constructing installations which it is not intended to use; constructing dummy airfields; putting up dummy guns or dummy tanks; giving large strong points to a small force; transmitting false information through newspapers or radio; making use of the enemy’s watchwords, wireless code signs and tuning calls to transmit false instructions; pretending to communicate with troops or reinforcements which do not exist; moving landmarks; removing from uniforms the badges indicating the grade, unit, nationality or speciality; giving the men of a single unit badges of several different units so that the enemy thinks that he is facing a bigger force; inciting enemy soldiers to rebellion, mutiny or desertion, possibly taking with them arms and means of transportation such as aircraft; and inducing the enemy population to revolt against its government, etc.