The Russian invasion of Ukraine in 2022 is starting to boost defense contractors' revenues, as customers such as the U.S. government restock supplies shipped to Ukraine and countries around Europe arm themselves with an eye on Moscow's aggressions. U.S. defense contractors such as Lockheed Martin, General Dynamics and others expect that existing orders for hundreds of thousands of artillery rounds, hundreds of Patriot missile interceptors and a surge in orders for armored vehicles expected in the months ahead will underpin their results in coming quarters. New contracts to supply Ukraine directly - or backfill U.S. weapons sent to Ukraine - were signed late last year, and now revenue is flowing to the big defense contractors.