A Russian Yars RS-24 intercontinental ballistic missile system drives during the Victory Day parade, marking the 71st anniversary of the victory over Nazi Germany in World War Two, at Red Square in Moscow, May 9, 2016. Grigory Dukor/Reuters

The Kremlin has dusted off Soviet-era civil-defense plans and upgraded bomb shelters in major cities as anti-American rhetoric dominates the airwaves in the wake of a mistaken U.S.-led coalition bombing of Syrian troops last month.

The United States and Russia ostensibly have been cooperating in Syria on routing the Islamic State group but still are on opposite sides when it comes to preserving the regime of Syrian President Bashar Assad. Relations between Moscow and Washington already had soured, especially in the wake of the 2014 Russian annexation of Crimea from Ukraine.

In recent months, the Cold War rhetoric has been escalating in a bid to divert attention from the country’s economic situation.

“Most people believe that the Third World War has begun, but right now we are still in the cold phase of the war, which may or may not turn into a hot war,” Lev Gudkov, head of the Russian polling group Levada-Center, told the Wall Street Journal. “And during war, you have to support your country’s authorities.”

Igor Zuyev, whose company builds bomb shelters, told the Journal business is booming, with shelters going for $24,000 for a family of four.

“When the situation started to heat up, particularly after the events of Crimea, a few months later people went mad, the demand was furious,” Mr. Zuyev said. “Demand has been rising ever since.”

Rhetoric also has been ratcheted up against Turkey, Ukraine and domestic opposition.

Russia held four days of emergency drills earlier this month involving 40 million Russians, including more than 200,000 specialist rescue units and 50,000 pieces of equipment. The drills were the biggest since the collapse of the Soviet Union. Videos showed emergency workers in hazmat suits checking the ventilation in bomb shelters and students trying on gas masks.

RIA Novosti reported recently officials have taken an inventory of underground spaces in Moscow in preparation to shelter the population from a chemical or nuclear attack.

“Russia is sick of America’s arrogant lies,” commentator Dmitry Kiselyov said after the latest Syrian peace plan collapsed.

“For Russia the breakdown of diplomacy around Syria is a symbol of the dysfunction of the world order established by the U.S. after the Cold War,” Fyodor Lukyanov, chairman of the Presidium of the Council on Foreign and Defense Policy, told the Journal. “For Americans, it’s that the Russians are just misbehaving.”

Peace activist Cindy Sheehan, whose soldier son was killed in Iraq, said in a Global Research blog post the United States is interested only in installing a “puppet” government in Damascus, and called provoking Russia “the height of arrogance and stupidity.” She warned if, as Democratic president nominee Hillary Clinton has proposed, a no-fly zone is imposed over Syria, all-out war with Russia would ensue.

Russian President Vladimir Putin has threatened to cancel an agreement with the United States signed in 2000 that provides for the disposal of weapons-grade plutonium. Russian Foreign Minister Sergei Lavrov called the withdrawal necessary because NATO forces have been bolstered along Ukraine’s border with Russia.

“The decision that has been taken by us is a signal to Washington,” Lavrov said.

The U.S. has called the decision disappointing.