SCOTUS June 2012 ruling re: ACA; penalty vs. tax

Hi,

I have a Constitutional question I'm hoping you can answer for me.
Here's my three-part question:

In SCOTUS' June 2012 ruling, it said the federal govt does not have the power to enforce ACA via penalties, but it could enforce via taxes.

But if ACA was written with penalty, not tax, and penalty is unconstitutional, then:

1) shouldn't SCOTUS' ruling have been unconstitutional [as written]?

2) Does SCOTUS have the power to "correct" defective law with a ruling?

3) Shouldn't Congress have to rewrite and pass ACA ?

Regards,
Matt Wisner