Yes, such a visa is needed. These are the conditions for staying in the US territory after the events of September 11. Even transit passengers now need to be vised.

Even if you do not leave the airport and do not leave the plane - in any case you need a visa in the US.

Any transit through the US territory requires a US visa, either transit or normal, even if you do not leave the airport and will be there only a couple of hours. Without a visa, you will not even be put on a flight back in Moscow.