[rayiner]

You can't enforce many regulations at the state level, even if people want them, because the Constitution forbids discriminating against out of state commerce or citizens. If Californians wanted to have single payer health care, their system would be very susceptible to abuse because people should could cross the border when they got sick. Then Arizonans get the best of both worlds--they don't have to raise taxes to pay for healthcare, but they can still get the service if they need it. Same thing with environmental regulations. Even if everyone in California voted to have environmental regulations, that just creates an opening for goods manufactured in environmentally harmful ways in Arizona to undercut California goods in price.

Citizens don't really have the freedom to choose on issues like that unless they have the freedom to close their markets to people who do not play along. The Constitution takes away that freedom.