The Supreme Court heard oral argument earlier this week on the legality of President Donald Trump’s Executive Order producing a moratorium on entry into the US from certain selected nations.  Neal Katyal, representing those arguing to keep Trump’s EO blocked,

says Congress previously has rejected exactly the kind of nationality-based ban that Mr Trump has implemented.

Whether or not that’s true, though, is irrelevant.  All that the Court can consider (aside from what is in the Constitution, which is always before the Court, and what’s in the Executive Order before the Court today), is what Congress has done this time.  Past actions are irrelevant, particularly since what Congress does today that differs or outright contradicts what Congress did yesterday overrides yesterday’s action.