Separation of powers - rather than reveal any secrets, the DOJ could simply either not contest the case, or in the most extreme measure I wish some POTUS would employ, not even go into court on it. To suggest that it can kill citizens just to “protect state secrets” is (1) Constitutionally silly and (2) suggests the state is willing to employ unnecessary steps to protect those “secrets” (of course the DOD/DOJ/FBI/CIA bureaucrats reveal secrets, anonymously, to “the press”, every day, even when there is no formal decision those secrets have become declassified).
Using the rules they employed to redact documents. States secrets is a broad brush.