Can U.S Citizen travel from Paris, France to USA?

It is called Paris, NOT Paris France, London is London Rome is Rome, everyone in the world knows this except it would appear Americans, We know where the cities are.

Trump has a private plane + Air Force one.. Anyway he cancelled the travel in Europe.

Travel is currently banned from Europe to the US for 30 days. Currently, you could come back; however, there is a very real risk of the ban being extended beyond 30 days in which case you would not be allowed to return. 

Until the ban is lifted, the only way you’re getting to Paris is to fly to London and then get the Eurostar train to Paris.

As you may imagine, short-notice flight bookings between the UK/Ireland and the USA will now likely be fully-booked due to overwhelming demand. 

If you purchased travel insurance before Trump’s announcement, then you should be able to cancel your visit and claim from insurance (less any deductibles) for any costs which you cannot get refunds for. 

But by the end of April, Covid-19 may well be just as commonplace in the USA as in Europe, so the ban would then be utterly pointless and may have been lifted. By then you might also have caught it and recovered.

The ban is for 30 days, announced Wednesday. But nobody knows if Trump will extend it beyond that. It's anybody's guess.