Hmm. Maybe. But it isn't necessary. Federal law enforcement is a pretty novel thing. State institutions have parity. There's no technical reason not to go back to that, though it would be a rather radical restructuring.
The US is far more connected than it used to be. It is much harder to treat everything as a matter for individual states. At the very least, state institutions need to coordinate -- exactly the kind of job for which a federal institution is ideal.