Alec Baldwin is blasting Nora Ephron in the same “Divorce” section of the Huffington Post which she launched last week. In Baldwin’s post, “Mum’s the Word for a Smarter Divorce,” he blasts “Dora,” who “simply cannot shut up about her anger, her betrayal . . . and her bottomless contempt for her ex,” whom he calls “Cal” — believed to be Carl Bernstein, Ephron’s second husband. She’d posted an excerpt from her book “I Remember Nothing” about her pain when Bernstein cheated on her in the ’70s. Baldwin writes, “Thirty years have passed and this woman . . . seems incapable of one of the most essential components of a ‘successful’ divorce, and that is forgetting . . . if they gave prizes for bashing your ex, [Dora] would have won the Pulitzer, Nobel and screenwriting Oscar.” Ephron fired back to Page Six with a line about Baldwin’s own ugly divorce: “I’m afraid that Alec, whom I love, has confused me with Kim Basinger, which is the first time anyone has ever done that.”