Cite, please.
Cite what? The non-existent clause in the Constitution that authorizes the FedGov to even run an organization like the BATFE? How do you quote something that doesn't exist? Absent the power being delegated to the FedGov, they can take no legitimate action. Hence, everything the BATFE does, is illegal.
You REALLY need to figure out what the whole Constitution thingie did. You don't appear to have a clue.