The governor of the state by virtue of his office, shall be commander-in-chief of the national guard, except of such thereof, as may be at times in the service of the United States. No armed military force from another state, territory or district shall be permitted to enter the state of Idaho for the purpose of doing military duty therein, without the permission of the governor, unless such force has been called into active service of the United States, and is acting under authority of the president of the United States.