Sforno on Leviticus 26:25/ספורנו על ויקרא כ״ו:כ״ה

1והבאתי עליכם חרב, as happened repeatedly during the periods when Israel was governed by its kings even though the Temple was standing. Kings II 8,12 describes a meeting of the prophet Elisha with King Ben Haddad of Aram (Syria) in which the prophet tells the king that the reason he is weeping is because he foresees the death and destruction which this king will cause his homeland.

2נוקמת נקם ברית, vengeance for violating the covenant, the very vengeance which is mentioned in the Book of the Covenant, in the words of our sages (Ketuvot 30) “even though the institution of the Supreme Court became void, the penalties which this court was authorised to hand out have not become void.” [if someone guilty of such a penalty which could not be administered because we are in exile, forfeits the atonement which administering the penalty would grant him, so that he is in fact much worse off seeing the court could not convict him. Ed.]

3ונתתם ביד אויב, as happened to the Ten Tribes who were exiled by the King of Assyria.