[butterdezillion]

What was the context for that quote? (It was a quote, wasn’t it?) Why was intrastate commerce considered necessary to make a regulation of interstate commerce effective in that particular case?

[Lurking Libertarian]

What was the context for that quote? (It was a quote, wasn’t it?) Why was intrastate commerce considered necessary to make a regulation of interstate commerce effective in that particular case?

It was a medical marijuana case. California law says that people with a doctor's recommendation can grow and smoke marijuana. Scalia said (and yes, that was a quote) that Congress has banned the interstate market for marijuana, and that the only way to successfully do that is to ban possession of all marijuana everywhere by everyone, because otherwise marijuana legally grown in California could be shipped out of the state before anyone could stop it.

[Ken H]

What was the context for that quote?

You can read Scalia's decision at the following url -

http://www.law.cornell.edu/supct/html/03-1454.ZC.html

Here is one example of how Raich has affected guns. From wikipedia:

"Not long after the decision in Raich, the Court vacated a lower court decision in United States v. Stewart and remanded it to the court of appeals for reconsideration in light of Raich. In Stewart, the Ninth Circuit had held that Congress lacked the Commerce Clause power to criminalize the possession of homemade machine guns."

http://en.wikipedia.org/wiki/Gonzales_v._Raich