Relations between the two are currently fairly good, and war between the two countries is seemingly unlikely. That being said, the two have had their share of territorial disputes, and at this point it is probably not a good idea to consider any dispute with China dormant.
Both Russia and China would have their own advantages and disadvantages in a war. The Russian military has gone to war numerous times in the last twenty years, in Chechnya, Georgia and now Ukraine. Russian forces, although often ill-trained and ill-prepared, are resilient and capable. Russia also holds a technological edge over China—for now, anyway.
The flip side is that Russian equipment, on balance, is fairly old. Russia’s economy is also less than a fifth of China’s, which will chip away at her strategic position. Another issue is as old as Russian power: much of the country’s military lies west of the Urals and would need to be sent east by air and rail.
China’s main advantage would be that the bulk of the People’s Liberation Army would be relatively close to the theater of operations. The PLA is also larger than the Russian military with fewer distractions—such as NATO or a restive Caucasus—that require an armed presence.
(This first appeared in 2015.)
On the other hand, Chinese forces have been unbloodied in war since 1979. The PLA’s grasp of the new warfare invoked by the Revolution in Military Affairs is notional and academic at best. And, despite the growing ranges of Chinese weapons, European Russia would be largely out of reach of the PLA.
Thus, the Russian side would seek to exploit its advantages in weaponry and experience. With regards to the former, here are 5 Russian weapons of war China should fear.
PAK FA Fighter
PAK FA—or Perspektivniy Aviacionniy Complex Frontovoi Aviacii—is Russia’s first fifth-generation fighter design. Helmed by the famous Sukhoi bureau, PAK FA  has been in development since April 2002.
PAK FA will be a multi-role aircraft capable of both air superiority and attack missions. The aircraft will have both an active electronically scanned array radar and an electro-optical sensor to track and engage targets. It will be a stealthy plane by design, with flattened and faceted surfaces designed to lower the aircraft radar signature.
PAK-FA is capable of carrying up to six long-range air-to-air or air-to-ground missiles and bombs in an internal weapons bay, giving it potent killing power while remaining difficult to detect by radar. Production is set to begin in 2017, and Russia intends to purchase between 400 and 450  PAK FA fighters between 2020 and 2040.
Tu-95 Bear strategic bomber
The Tupolev Tu-95 “Bear” turboprop bomber is a nuclear cruise missile carrier, capable of being armed with conventional land-attack cruise missiles. The Bear has astonishingly long range, regularly making the flight from Ukrainka Air Base in Siberia to the California coastline.
Although an obsolete design, the Bear is still a capable platform for conducting standoff cruise missile attacks. The Bear doesn’t have to get anywhere near Chinese airspace to loose a salvo of up to eight Kh-101 cruise missiles against Chinese targets. The Kh-101 is Russia’s new stealthy, precision-guided conventionally armed cruise missiles with an estimated range of 2,700 to 5,000 kilometers .
Flying from Engels Air Base in European Russia, a Bear could easily travel 2,000 kilometers and then release a salvo of Kh-101s against targets across China, even as far south as Hainan Island.
Tu-160 Blackjack strategic bomber
The four engine, swing-wing Blackjack is Russia’s most capable bomber, able to operate at night and adverse weather conditions carrying a large internal payload of laser-guided bombs or cruise missiles. The Blackjack can carry 22 tons of ordnance in two weapons bays.
While the Tu-95 Bear would launch cruise missiles from outside the enemy air defense network, the Blackjack is designed to penetrate defenses flying at low altitude. The Blackjack is also armed with the new Kh-101 long-range cruise missile. The missiles are carried internally on a rotary launcher, preserving the Blackjack’s stealthy profile.
While the prospect of an aging, lumbering bomber lingering outside China’s national borders and flinging deadly modern cruise missiles is scary enough, the prospect of the world’s largest heavy bomber flying over Chinese territory, evading air defenses and striking targets should give Beijing pause.
Su-35 Flanker Fighter
Meant as a stopgap measure between the aging Su-27 fighters and the PAK FA, the Su-35 is a credible fighter in its own right. A blend of the older Su-27 airframe and modern aircraft systems and weapons, the Su-35 will form the sharp end of the Russian Air Force until the PAK-FA appears in significant numbers.
A multirole fighter bomber, the Su-35 is superior to any operational Chinese fighter. Avionics, propulsion and weapons systems are all superior, as are the NPO Saturn AL-41 engines. Radar-absorbent materials are used in the construction of the airframe. The plane is a flying arsenal, featuring a stunning 14 hardpoints for carrying weapons, jammers, fuel tanks and added sensors.
The proof of the Su-35’s superiority is that China itself is attempting to purchase Su-35s . Until the J-20 and J-31 start rolling off the assembly lines the only possible equal to the Su-35 would be… the Su-35.
T-14 Armata Tank
The next-generation tank for the Russian Ground Forces, Armata  is a long-overdue replacement for the T-72/T-80/T-90 series of tanks. Armata is a totally new design, bigger, heavier, with more protection and better armament.
Should a Sino-Russian war include ground combat, Armata is Russia’s best bet for holding ground and conducting rapid counterattacks into Manchuria. Armata outclasses China’s frontline Type 99 tanks, which are based on the T-72.
Armata is longer than the T-72 series, with an extra road wheel to accommodate a full crew compartment and future growth. Armor appears to be composite laid out in a modular fashion, making it more easily repairable. Weapons consist of an improved 125-millimeter main gun, 12.7-millimeter remotely operated machine gun and 7.62-millimeter coaxial machine gun.
Armata is actually a family of vehicles, including the T-15 Heavy Infantry Fighting Vehicle. Heavily protected, the T-15 is designed to safely transport Russian infantry across battlefields laden with anti-tank weapons.
Kyle Mizokami is a writer based in San Francisco who has appeared in The Diplomat, Foreign Policy, War is Boring and The Daily Beast. In 2009 he co-founded the defense and security blog Japan Security Watch.