If the governor proclaims that a disaster emergency exists in the event of actual enemy attack upon the United States or the occurrence within the state of a major disaster resulting from enemy sabotage or other hostile action, or from man-made or natural disaster, it shall be the duty of the city ESDA to cooperate fully with the state ESDA and with the governor in the exercise of emergency powers as provided by law.
(`79 Code, § 32.425)