"I will ..." is a nonpast tense, though. The semantics is future, but tense is a matter of syntax. The modal verb which establishes future semantics it not in

"I will ..." is a nonpast tense, though. The semantics is future, but tense is a matter of syntax. The modal verb which establishes future semantics it not in a future tense; it is in its dictionary form: to will. In archaic English we can say things like "As I will it, so it shall be" where the verb isn't acting as a modal. The modal will comes from that one, I believe.