&gt; It's no less connected to interstate commerce than plenty of other things that have been upheld that way. 

Has any *Executive* unilateral action unsupported by Congressional action been upheld on that basis? 

It seems that argument (which, while I agree with you about it being less of a stretch than others, is absolutely asinine) would be grounding for Congress to pass a law like this, is there precedent for the President to act in the absence of a law being passed on the basis of Congress’ authority to regulate interstate commerce?