Is there a diference between “should” and “will”?

John Adler writes about a WaPo poll that shows 67% of respondents want the Court to strike down the mandate, or strike down ACA in its entirety:

Combined with other recent poll results, it’s hard to see how the finding headlined by the Post is all that significant.  It’s even harder to understand why some progressive partisans think the President should campaign against the Court if it strikes down the mandate as he seeks reelection.  Polls are consistently finding that most Americans believe the Supreme Court should and will strike down the mandate.  If anything — and I stress if anything – this would suggest there’s more political risk to the Court from upholding the mandate than from striking it down.  In the end, however, the justices should not base their votes on public opinion polls, but on what they believe the Constitution requires.