No other country has anything to teach the USA. The USA is unique and special for a large number of reasons and so foreign methods won't work here. If I recall they even drive on the other side of the road in the UK, that will never catch on here.
Cars on a Monday. Lorries and HGVs switch on Wednesday. All remaining traffic on the Friday.
Done!
(Note that it was a follow up to patently satirical parent comment, but it does remind me that Sweden made the change on 3rd Sep 1967)