[carradjm]

They absolutely should be able to express their ideas, as long as they do so in a peaceful and non-threatening way.

[bluGill]

If the idea is not peaceful though, even though the expression is? "We should change the law to make murder legal" is a peaceful statement, but if it catches on...

[ameister14]

What about burning or hanging someone in effigy? That's pretty threatening, but doesn't actively display intent.