The deal, which Mr. Putin called an “epochal event,” solidified a relationship between China and Russia that had been warming since Mr. Xi assumed power in 2012, as Mr. Xi and Mr. Putin have found common cause.
“The Sino-Soviet rift that brought the two countries to the brink of nuclear war in the ’60s has been healed rather dramatically,” said Strobe Talbott, president of the Brookings Institution and the chairman of Secretary of State John Kerry’s Foreign Policy Advisory Board.
Ostensibly on the same side during the Cold War, the Asian neighbors even then competed for global influence with their divergent brands of communism. They fought a brief but explosive border war in 1969, and later took opposite sides in conflicts in Vietnam and Afghanistan.
They have similar views of the United States, however, including opposition to its unilateral military actions in Kosovo, Iraq and Libya, and wanted to “take Uncle Sam down a peg or two,” Mr. Talbott said. Mr. Putin, in particular, wanted to make a point of showing that the United States and its NATO partners were in decline.
The deal offered a lift for the Russian economy, he said, and for Mr. Putin, China’s validation would improve Russia’s world image.