Three U.S. officials confirmed to ABC News on Sunday that Biden had authorized Ukraine to use the ATACMS -- officially called the MGM-140 Army Tactical Missile System -- in Russia

After U.S. President Joe Biden gave the go-ahead for Ukraine to wield long-range American missiles deep inside Russia, as a Newsweek map illustrates, questions remain over just how much of a difference this will make as Moscow gains in the east and a new U.S. presidential term approaches.