The party is marking the 70th anniversary of its establishment of the state, an important milestone because the PRC has now outlasted the Soviet Union, which endured for 69 years.
But it comes at a time of intense pressure on the party's leadership.
The party is locked in a protracted trade war with the United States which coincides with a tangible slowdown in the economy. At the same time, protesters in Hong Kong are demonstrating against creeping Chinese restrictions of their freedoms and are warning Taiwanese that it could happen to them if China were to try to offer a "one country, two systems" deal to that island.
"This parade will highlight Chinese military power, at a time when Sino-American relations are deteriorating and international arms control treaties are being called into question," said Antoine Bondaz and StÃ©phane Delory of the Fondation pour la Recherche StratÃ©gique in France.
"Our research indicates that unprecedented conventional and nuclear ballistic capabilities will be paraded, some for the first time, demonstrating the quantitative and qualitative modernization of China's ballistic arsenal," they wrote in a research note. "Highly rapid, even hypersonic weapon systems could also be shown, illustrating that China is, in some respects, at the forefront of global innovation."
China's most recent parade was in 2015, marking the end of the Pacific War and the victory over Japan, and was attended by foreign leaders including then South Korean president Park Geun-hye and Russian leader Vladimir Putin. Foreign leaders are expected again at this parade, but Beijing has not announced who will be coming.
It has announced some details, however.
The parade will feature 59 phalanxes, about 15,000 soldiers, 160 aircraft and 580 other pieces of weaponry and equipment, Maj. Gen. Cai Zhijun, deputy director of the military parade office said. About 300,000 civilians will participate in the parade.
But Defense Ministry spokesman, Wu Qian, dismissed the idea that the People's Liberation Army, the military force that is beholden by the Communist Party, is "flexing its muscles" to send a message to the outside world.
"Over the past 70 years, the development of the China's armed forces is obvious to all. We had no intention, nor felt the need to flex our muscle through a military parade," he said at a briefing about parade preparations last week. "Over the past 70 years, the world also witnessed the contributions made by the China's armed forces. The stronger we become, the more contributions we can make to world peace."
Authorities have carried out three parade rehearsals centered on Tiananmen Square in recent weeks. People have reported seeing war planes, tanks, amphibious assault vehicles, anti-ship and antiaircraft missiles, and supersonic and stealth drones.
Here is some of the firepower we can expect to see at Tuesday's parade:
• The DF-41 intercontinental ballistic missile
The hardware of the People's Liberation Army's Rocket Force is attracting particular attention, amid signs that the Dongfeng-41 next generation ICBM may make its debut at the parade. "Dongfeng" means "east wind."
The DF-41 is a three-stage, solid-fuel missile with a range of about 7,500 miles, meaning it could strike any target in the United States.
It can carry up to 10 independently targetable nuclear warheads, Xu Guangyu, a senior adviser of the China Arms Control and Disarmament Association, told the Global Times, a hawkish party-affiliated newspaper.
The Global Times quoted military experts saying that the fourth-generation nuclear DF-41 missile is "basically at the same level as the seventh-generation nuclear missiles being developed by the U.S. and Russia, and (has) attained a world-leading level in terms of technologies, materials and processes."
Because the DF-41 missile can be armed with a relatively large number of multiple warheads, it "gives China the opportunity to significantly increase the number of deployed warheads without increasing the size of its ballistic arsenal," Bondaz and Delory wrote in their note.
Furthermore, the missile can carry decoys and penetration aids, boosting its offensive capabilities, and can also change course and trajectory in flight, helping their evade antimissile defenses, they said.
People watching the parade rehearsals took photos of what appeared to be DF-41 missiles, covered by camouflage canvas, on trucks on the streets of central Beijing. But the parade organizers have declined to confirm if the DF-41 missile will appear on Tuesday.
"Everyone please wait and see, and I believe our journalist friends will not be disappointed," Maj. Gen. Tan Min, one of the commanders of the parade, told reporters.
• The DF-17 hypersonicballistic missile
The Dongfeng-17 is a short-to-medium-range missile that can launch a hypersonic glide vehicle, or HGV, which Bondaz and Delory say "would be a major first."
"The emergence of such a system would have a considerable impact, highlighting China's progress in designing hypersonic nonstrategic gliders, a segment in which Russians and Americans are lagging behind," they wrote.
The missile appears to be capable of exceeding the speed of sound and penetrating U.S. missile shields, and has a maneuverable reentry vehicle, so it could shift targets in flight.
That would make it less vulnerable to interception by other countries' defense systems, the South China Morning Post reported, quoting a source from the state-owned China Aerospace Science and Industry Corporation.
"And the DF-17 will be capable of delivering both nuclear and conventional payloads," said the paper's source, who was not named.
When China carried out the first tests at the end of 2017, the DF-17 missile successfully completed its ballistic flights and reentered the Earth's atmosphere, using the HGV during the glide phase, The Diplomat reported at the time. It landed "within meters" of its intended target during that test, the website reported, quoting American intelligence sources.
• The DR-8 unmanned aerial vehicle and the Sharp Sword stealth attack drone
Photos from the parade rehearsals have prompted speculation that it will include two types of unmanned aerial vehicles, or drones. China has been heavily investing in drone technologies and making technological advances.
Experts have spotted images of what appears to be a DR-8 reconnaissance drone, which can reach as far into the western Pacific as the American territory of Guam, but has been in service for some time.
More concerning is the Sharp Sword, an attack drone that is not just at UAV but a UCAV: an unmanned combat air vehicle. The aircraft can carry missiles or laser-guided bombs. It expected to enter service before the end of the year.
"The U.S. has been using drones armed with missiles and guided bombs for many years in the war against terrorism," wrote Sam Roggeveen, director of the international security program at the Lowy Institute in Sydney.
These longer-range aircraft and missiles seem designed with the U.S. military in mind, analysts say.
"The PLA Rocket Force has placed particular emphasis on developing dangerous long-range anti-ship missiles that can keep the U.S. Navy at a safe distance," the Defense Talk industry publication reported, "so the Sharp Sword's ability to further extend that range only places enemy ships in all the more peril."
• J-20 stealth fighter jets
The PLA Air Force recently released video of seven J-20s flying in formation, prompting speculation they would fly over Tiananmen Square as part of the parade.
"To truly achieve peace, defending our homeland is not enough. We must not only defend but attack," said Yang Wei, the J-20's chief designer, in the video.
Pairs or small numbers of J-20s have appeared in previous parades, but the fact the Air Force is ready to fly seven of them is significant and suggested they are ready for combat, according to analysts.
"A considerable number of units are probably ready to fly the J-20," Wang Ya'nan, chief editor of Aerospace Knowledge magazine, told the Global Times.
"If seven J-20s are sent simultaneously into battle, they would have a significant striking capability with their air-to-air and air-to-surface weapons," Wang told the paper. They would be able to strike enemy targets deep in hostile territory, he said.
Designed for enhanced stealth and maneuverability, the J-20 has the potential to provide China with a variety of previously unavailable air combat options and enhance its capability to project power, according to the China Power Project at the Center for Strategic and International Studies.
The Pentagon says China views stealth technology as a core component in the transformation of its air force from "a predominantly territorial air force to one capable of conducting both offensive and defensive operations."
• The H-6N, a new bomber
The H-6N, a new version of China's long-range strategic bomber, also appeared during parade rehearsals. But photos of the H-6N posted on Weibo, China's answer to Twitter, appeared to show it did not have a bomb bay, causing analysts to wonder if it had been deleted from the photos.
The photos did, however, show large, visible missiles mounted on the bomber. The War Zone blog suggested these could be DF-21 anti-ship ballistic missiles, which it said would give the bomber "an impressive standoff capability against large enemy warships, especially aircraft carriers."
Other observers noted the bomber had an aerial refueling receptacle. That will enable the aircraft, which was modeled on the Soviet Tu-16 jet bomber, to carry out in-flight refueling - significantly boosting its operating range compared to its predecessor, the H-6K the South China Morning Post reported.
• Type 15 tanks
China's lightweight Type 15 tanks also look set to make an appearance in the parade. The tanks have been commissioned by the Chinese military, according to China's latest national defense white paper, and will appear in public for the first time at Tuesday's parade.
It is armed with a fully-stabilized 105mm rifled gun and an effective firing range of two miles. The tank weighs between 33 and 36 tons, making it more mobile than a standard battle tank, which usually weight about 50 tons.
"Mobility and rapid redeployment is the key factor of this new combat vehicle. It is intended mainly for reconnaissance and infantry support operations," according to Military Today. "It can be airdropped and operate in areas, such as mountains, jungles and river regions, that are not accessible to heavier main battle tanks."
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