so let me ask you this:
the CA law is basically designed to prevent local and state enforcement of federal law. It doesn't directly contradict federal law (like Arizona vs. the US 2012), but skirts it.
it is basically a jurisdictional battle
likewise, states have refused to enforce federal narcotics laws, and have legalized weed on the state level
Correct on both cases.
but should states be able to pass laws that say "we will not longer prosecute murder" or "we won't arrest people for rape anymore"?
Sure. That's kinda the whole point of states having plenary police power. They get to decide what is and what isn't a crime in their jurisdiction. Now I think this would be a horrible idea on a policy level, but perfectly legal.
Or maybe the state can pass a law that says it won't stand in the way of local authorities shutting down newspapers and arresting people for political speech.
Once again the 14th Amendment comes into the picture since it incorporates the Bill of Rights into state law in all states. But here's the big difference. Local authorities, what ever form that might take e.g: town, city, county, etc., are not sovereign. They exist as a creation of state law and thus every exercise of power they make is an exercise of state power. As such they are bound by the same limitations as the state government, and conversely are required to do what the state tells them. That's why there are so many preemption laws. The several states on the other hand are independently sovereign and don't derive their authority from the federal government.
pretty sure you would say "such laws would not be permissible"
For the second one yes, and I explained why.
why?
because they violate fundamental sections of the US Constitution
Nothing in the US Constitution requires states laws to be identical to federal ones, (for instance regarding narcotics), nor in assisting the federal government in enforcing law that they have enacted.
...and there is this thing called the Supremacy Clause
Sure, which you seem to have a misunderstanding of. The SUpremacy Clause doesn't mean that the states are forced to do what the federal government wants. It simply means that when state and federal law, including the constitution, conflict the federal law is the one that takes effect.
finding loopholes and clever schemes to allow for lawlessness at the state level is wrong, both ethically and (ultimately) legally.
What lawlessness? Having different laws and priorities then you would prefer is not the same thing as lawlessness. In fact, regarding sanctuary policies, the largest reason they exist is to promote law and order. They want people to be able to go to local law enforcement to report crimes without being deterred from doing so by fear of being handed over to ICE.
We have borders and immigration law for a reason,
Sure. And the states have laws around state participation and enforcement of those for their own reasons.
just as we have narcotics laws.
And states are allowed to execute their own judgment over what their own controlled substance laws look like as long as they aren't preventing the enforcement of federal law.
If the Democrats want to continue supporting lawlessness,
Everything the democrats support is strictly within the law, even if it doesn't match your own personal policy preferences. Also, is there a reason you didn't respond to my question about the states that have laws purporting to forbid the enforcement of certain firearm laws by anybody, including the federal government?
they will continue losing elections,
Considering the Republicans nominated a felon who was then elected, I'm not sure there is any connection between law and order and electoral success.
and all of this will be corrected.
How, within the bounds of the Constitution, would it be corrected?