"I am deeply concerned over increasingly visible signs of the militarization of politics and thinking in the modern world... even though the military route again and again leads to a dead-end," Gorbachev wrote in an article printed in the Russian government daily Rossiiskaya Gazeta.
The presidential campaign will have to address the main policy issues facing the U.S. - the country's role in the world, its aim to lead in international affairs, counter-terrorism, and nuclear non-proliferation, all of which are inextricably linked to the Iraq war, he said.
The U.S. administration under George W. Bush has shown a tendency to "seek to address these problems primarily through threats and pressure. Will the candidates develop an alternative approach to these most crucial problems? This is now the main question."
Gorbachev said current talks on North Korea's nuclear disarmament, which Washington started after several years of belligerent rhetoric, is an example of an alternative, more effective policy.
He also stressed the dispute with Iran over its controversial nuclear program cannot not be resolved by threats.
Gorbachev hailed Republican candidate John McCain and Democratic hopeful Barak Obama for backing appeals to abolish nuclear weapons.
In 1985, Gorbachev and U.S. President Ronald Reagan reached a historic agreement on eliminating medium- and shorter-range missiles, which was followed by an agreement on a 50% reduction in strategic offensive weapons. Thousands of nuclear warheads were subsequently destroyed.
Gorbachev criticized the vast level of borrowing by the U.S. government to prop up the economy, and linked the country's economic downturn to excessive military spending, which he said has caused a budget deficit "larger than at the height of the Cold War."
He stressed that neither of the candidates for the November election has yet raised the alarm over growing military spending in America.
"The subject of military spending has literally been shrouded in a curtain of silence. This taboo must be lifted," he said.
U.S. military spending was reported to hit $547 billion in 2007, and accounted for 45% of the world total.
The U.S. accounts for 50% of the world's output of arms and military equipment, Gorbachev said. "It runs over 700 military bases across the world and plans to build more as if the Cold War were not a thing of the past, and the country were surrounded by enemies."
The next U.S. leader, Gorbachev said, will have to decide whether America will be an empire or a democracy, and to choose between global hegemony and international cooperation.