That isn't really possible because American Constitution expressly prohibits it. There is no realistic possibility of modifying the Constitution to allow it either.

As far as the US Federal government is concerned it has little practical relevance.

No, lol! That would hamper the USs strongest asset: consumption!

which is likely being hampered anyways due to corporate greed in the financial sector - it is going to be interesting to see the actual breaking point for leveraged consumption