(620 ILCS 10/2) (from Ch. 15 1/2, par. 180)

Sec. 2.

Immediately upon the existence of a state of military emergency, and
coincident with the duration thereof, the Department is vested with
emergency police power to prohibit, restrict and control the initiation of
non-scheduled civil aircraft movements, including the assignment of flight
priority classifications, to the extent that it is requested to do so by
military or civil authority of the federal government as required to
supplement otherwise existing air traffic control facilities in order to
achieve the degree of military air defense effectiveness determined by the
federal military and defense commander to be required under the
circumstances and conditions obtaining at any time during the existence of
the military emergency.

(Source: Laws 1955, p. 242.)