source: the Clause protects liberty by preventing governments from enacting statutes with "manifestly unjust and oppressive " retroactive effects. Calder v. Bull, 3 Dall. 386, 391. # the law threatens the kinds of harm that the Clause (of the Constitution) seeks to avoid.
target: the Clause protects liberty by preventing governments from enacting statutes with "manifestly unjust and oppressive " retroactive effects. Calder v. Bull, 3 Dall. 386, 391. And since The law has "manifestly  unjust and oppressive " retroactive effects. the law threatens the kinds of harm that the Clause (of the Constitution) seeks to avoid.