Many thanks for the links and explanations. Let me ask a very simple question. If this clause guarantees that as citizens we have privileges or immunities that shall not be messed with, then how can they make laws that infringe on those privileges or immunities without them being immediately struck down as unconstitutional?
I guess the short answer I can think of is that they do, because they don't care, and they know it would be too expensive or time consuming for most citizens to fight it, and there is no penalty to them for doing so.
If we were successful in setting a stiff penalty under law for passing any legislation that was thereafter to be found unconstitutional, and made it a burden of the government to foot the bill for such challenges, I think a lot of these horrible leftist dream laws would never see the light of day, let alone be set to paper.