“In spook-speak, “I believe” means there is no direct evidence, no “smoking gun.””
In legal-speak, he would have to say “I believe.” If he said definitely “yes” he would have to present evidence, which he cannot.
Most of us can’t produce evidence of much of what we did in our personal lives last month, but we can believe what we did.
In legal-speak, he would have to say “I believe.” If he said definitely “yes” he would have to present evidence, which he cannot.
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He cannot present evidence because the evidence is classified, and to reveal any of it, or even present the appearance of certainty, would identify him and be his death warrant.