Every charter shall provide—
(a)
That the charterer shall carry on the chartered vessels, at his own expense, policies of insurance covering all marine and port risks, protection and indemnity risks, and all other hazards and liabilities, in such amounts, in such form, and in such insurance companies as the Secretary of Transportation shall require and approve, adequate to cover all damages claimed against and losses sustained by the chartered vessels arising during the life of the charter: Provided, That in accordance with existing law, some or all of such insurance risks may be underwritten by the Secretary of Transportation himself as in his discretion he may determine.
(b)
That the charterer shall at its own expense keep the chartered vessel in good state of repair and in efficient operating condition and shall at its own expense make any and all repairs as may be required by the Secretary of Transportation.
(c)
That the Secretary of Transportation shall have the right to inspect the vessel at any and all times to ascertain its condition.
(d)
That whenever the President shall proclaim that the security of the national defense makes it advisable, or during any national emergency declared by proclamation of the President, the Secretary of Transportation may terminate the charter without cost to the United States, upon such notice to the charterers as the President shall determine.