Ronald Reagan explained his strategy was an arms buildup that would leave the Soviets far behind, with no choice but to negotiate arms reduction. Finally, displaying his characteristic optimism, he praised liberal democracy and promised that such a system eventually would triumph over Soviet communism. Reagan appreciated the revolutionary change in the direction of the Soviet policy with Mikhail Gorbachev, and shifted to diplomacy, with a view to encourage the Soviet leader to pursue substantial arms agreements. He and Gorbachev held four summit conferences between 1985 and 1988: the first in Geneva, Switzerland, the second in Reykjavík, Iceland, the third in Washington,
Mikhail Gorbachev for five years. In July 2016, Gorbachev criticized the North Atlantic Treaty Organization amid escalating tensions between the military alliance and the Russian Federation. Gorbachev has accused NATO of preparing for a "hot" war against Russia, saying that "All the rhetoric in Warsaw just yells of a desire almost to declare war on Russia. They only talk about defence, but actually they are preparing for offensive operations." In June 2018, Gorbachev welcomed the 2018 Russia–United States summit between Vladimir Putin and Donald Trump in Helsinki, Finland. In October 2018, Gorbachev criticized President Donald Trump's threat to withdraw from the 1987