In order to extend to employees of the state, its political subdivisions and of the instrumentalities of either and to the dependents and survivors of such employees the basic protection accorded to others by the Old-Age and Survivors’ Insurance System embodied in the Social Security Act, it is hereby declared to be the policy of the Legislature, subject to the limitations of this chapter, that such steps be taken as to provide such protection to employees of the state and local governments on as broad a basis as is permitted under applicable federal law.