Over the past half year the West has increasingly taken note of the significantly heightened pace of both Chinese and Russian military spending and surprising leaps forward in terms defense tech advances.

Even when Chinese or Russian systems fail, as with recent news of a nuclear-powered cruise missile touted by Putin as having "unlimited range" but now apparently lost at the bottom of the sea, Western press takes notice, and a number of Pentagon officials have also warned especially of rapidly advancing Chinese systems.

Increasingly, the two powers are cooperating more directly as with Russia's upcoming military games, said to be the largest such exercise since the Soviet Union, where China is set to participate my sending a mass contingency of elite troops.

According to the South China Morning Post (SCMP) the People's Liberation Army (PLA) will participate by sending about 3,200 elite forces troops, along with 30 fix-wing aircraft and helicopters to the Russian-hosted exercises.

Russia's biggest military games in 35 years, called the Vostok 2018 exercises, are set to begin at the Tsugol training range in Russia’s Far East Trans-Baikal region on September 11, and are scheduled to go through the 15th.

Crucially, one major element to the games sure to attract the attention of Washington military planners is the inclusion of simulated nuclear weapons attacks. Both countries are among the world's major longtime nuclear armed powers, and both happen to be in the midst of soaring tensions with the United States — Russia the target of sanctions and wide-ranging accusations of election meddling, and China in a trade war that sees no signs of abating.

The SCMP cites one Beijing based military expert, Zhou Chenming, to explain that the PLA is seeking to gain greater military experience as its last major combat theater stretches all the way back to the Vietnam War.

Additionally, Zhou told the SCMP, “China also wants to show its support for Russian President Vladimir Putin, who is facing various diplomatic challenges, especially criticism from the US Secretary of State [Mike Pompeo] over Moscow’s annexation of Crimea.” The Chinese military expert further cited that the games' site location was chosen carefully and deliberately with this in mind.

“Putin wants to use the Russian military’s war games with the PLA to show its military muscle, but he doesn’t want to irritate the United States too much and raise the possibility of a misjudgment by the Trump administration, so he chose the less sensitive Trans-Baikal region in the Far East, far from US allies in Europe,” Zhou said.

In response to the impending Vostok-18 games Pentagon spokesman Eric Pahon said, "We urge Russia to take steps to share information regarding its exercises and operations in Europe to clearly convey its intentions and minimize and potential misunderstanding."

The US defense official further indicated the games will be closely watched by U.S. intelligence agencies due to Russia's willingness to simulate nuclear combat. "It's their strategic messaging," the Pentagon official said of both Russia and China.

There's also reports that both countries are experimenting with the development of smaller, tactical nuclear weapons, which of further concern for US defense preparedness.

Earlier this week Russian Defense Minister Sergey Shoygu announced the exercises would be the largest since the Soviet Union conducted its Zapad-81 maneuvers, which saw the deployment of hundreds of thousands of Soviet troops and logistics staff.

"This is the largest armed forces training event since the Zapad-81 maneuvers, it has acquired the status of an international exercise and is of unprecedented scale both in terms of spatial scope as well as the strength of military command and control entities, troops, and forces involved," Shoygu said, while also announcing the Chinese PLA would participate, as well as auxiliary units from the Mongolian armed forces.