Why no one is going to build a bridge between Alaska and Russia

The Bering Strait between Russia and Alaska is only about 50 miles. It would be very expensive to build a bridge across the Bering Strait, even thought there are a couple of islands in the middle (the Doimedes), which would take the price of construction down to about $105 billion (5 times the price of the English Channel tunnel). If such a bridge were built, you could drive from Los Angeles to Paris (or even Miami to Capetown). But this video gives all the reasons why this bridge will probably never be built.