The United States has “fallen behind on nuclear weapon capacity." I'd say any number more than zero is surplus to requirements.
One could also say: This man has not all cups in the cupboard (German idiom).
More cups than those who voted for him, however, that being the real puzzle and concern. (I am presuming your Germanicish idiom means the same as we say with "one sandwich short of a picnic", or various other alternatives such as "not the full shilling", or, more directly: "off his effing head". Still, I am sure it will all come out in the wash (and wash-day may be soon).
'More cups than those who voted for him.' Quite, Andrew. And it's to be supposed that those who voted for him do have much more weapons in their cupboards than those who did not.