China will start its war for a number of reasons:
  1. Regime Legitimacy
Very few people in China believe in communism anymore, including almost all of the 80 million members of the Chinese Communist Party.  The party itself is now a club for mutual enrichment.  The legitimacy of the party ruling China is derived from the notions that democracy does not suit China and that the party is the organisation best placed to run the country.  The latter is based on an ongoing improvement in conditions for the bulk of the population.  In the absence of economic improvement, some other reason must be found for the population to rally around the party’s leadership.  This may explain the sudden base-building that started in the Spratly Islands in October 2014. 
China’s public debt grew from US$7 trillion in 2007 to US$28 trillion in 2014.  This is on an economy of US$10 trillion per annum.  A high proportion of the economic growth of the last seven years is simply construction funded by debt.  The real economy is much smaller.
The Chinese government is likely to see the contracting economy and realise that issuing more debt won’t have an effect on sustaining economic activity.  Thus the base-building was accelerated to allow the option of starting their war.  This is a life and death matter for the elite running the party.  They are betting the farm on this.  If this gamble does not work out then there is likely to be a messy regime change.
  1. Chosen Trauma
Japan treated the Chinese as sub-humans during World War 2.  Before that, Japan starting mistreating China by attacking it in 1895, not long after they started industrializing themselves.  That was followed by Japan’s 21 demands on the Chinese state in 1915.  The Nationalist government in China started observing National Humiliation Day in the 1920s.  Then followed the Mukden Incident of 1931 and China’s start to World War 2 in 1937.
During the poverty of the Mao years, the Japanese were forgiven for World War 2. Mao and Deng were pragmatists and said that Japan couldn’t be punished forever.  China’s recent prosperity has allowed the indulgence of Japan-hating to be resurrected as a form of state religion.  National Humiliation Day is observed again on the 18th September.  The party has directed that television take up the theme of Japanese aggression.  Today 70% of prime time television in China is movies about World War 2.  There are at least 100 museums in China dedicated to the Japanese aggression of World War 2.
The regime generates and sustains anti-Japanese sentiment to give it the option to go to war.
  1. Being Recognised As Number One
The Chinese are a proud nation.  They actually resent the fact that the United States is considered to be the number one nation on the planet.  China also realises that to be recognised as number one, they have to defeat the current number one in battle.  This is why it won’t be just creeping increments in Chinese aggression.  They need a battle for their own psychological reasons.
This means that they will attack the United States at the same time that they attack Japan.  Because surprise attacks are more successful, it will be a surprise attack on US bases in Asia and the Pacific and perhaps well beyond.  This most likely will include cyber-attacks on US utilities and communications.
China has structured its armed forces for a short, sharp war.  Of any country on the planet, they are possibly the most prepared for war.  They have one year of grain consumption in stock and even a strategic pork reserve.  They have just filled up their strategic petroleum reserve of about 700 million barrels.
China’s war has nothing to do with securing resources or making their trade routes secure.  Some western analysts have projected those notions onto China to rationalise what China is doing.  The Chinese themselves have not offered these excuses.  To China it is all about territorial integrity, which is sacred and not the profane stuff of commerce.
  1. Humiliating The Neighbours
The importance of the Spratly Islands and the Chinese nine-dash claim is that it divides Asia. 
Nine-dash claim  (U.S. Central Intelligence Agency via Wikimedia Commons)
China claims that the whole of the sea within its claim is Chinese territory, not just the islands.  When China gets around to enforcing that claim, foreign merchant vessels and aircraft will have to apply for permission to cross it. Non-Chinese warships and military aircraft will not be allowed to enter it.  The Chinese claim extends to 4° south, almost to the equator.
The worst affected country will be Vietnam, which will be bottled up to within 80 km of its coast.  Japan realises that its ships from Europe and the Middle East will have to head further east before heading up north through Indonesia and east of the Philippines.  Singapore will be badly affected because the passing trade will drop off.
Japan will become quite isolated because its aircraft will have to head down through the Philippines to almost the equator before heading west. 
China ranks the countries of the world in terms of their comprehensive national power, which the Chinese consider to be the power to compel.  This is a combination of military power, economic power and social cohesion.  When it is enforced, the nine-dash claim will do a lot of compelling of China’s neighbours.
  1. Strategic Window
Chinese strategists see a window of strategic opportunity for China early in the 21st century, though they haven’t publicly outlined the basis for that view.  But we can make a good stab at it.  Firstly, an air of inevitability is important in winning battles.  While China is perceived to have a strong, growing economy that is crushing all before it, that perception of inevitability rubs off on China’s military adventures.  To use that perception, China has to attack before its economy contracts due to the bursting of its real estate bubble.  This explains the current rush to build the bases in the Spratly Islands. 
Another problem for China is that its aggression and increased military spending has caused its neighbors to rearm and form alliances.  China is better off attacking before its neighbors arm themselves further. 
Another consideration is the US presidential electoral cycle.  President Obama is perceived to be a weak president and the Chinese might rather attack before he is replaced.  President Obama has made the right noises, though, about Chinese irredentism and the coming war remains quite popular in the US military, in that the different services are jockeying for position, which means they have official blessing to the highest level.  President Obama does have some inconsistent policies that aid China, though, in that while a strong economy is needed to fight China, his administration is doing its best to choke the US economy with carbon dioxide-related regulations.  The two ends are mutually exclusive.
President Obama spent a period of his childhood in Indonesia and would have heard a lot of anti-Chinese sentiment (the Chinese were and are more successful merchants and shopkeepers) in those formative years.  As with Valerie Jarrett’s childhood in Iran, this will affect policy.
  1. Great-State Autism
This is a term created by the strategist Edward Luttwak to describe the fact that China is seemingly oblivious to the effects of its actions on its neighbours.  China sees itself as the center of the world and purely through the lens of its own self-interest. This has the practical result that China could not perceive the possibility of things not going the way it wants them to.  Luttwak also considers that the Chinese overestimate their own strategic thinking.  He says that China doesn’t have a strategy so much as a bag of stratagems, most of which involve deception.
  1. President Xi Jinping
While preparation for this war started in the 1980s, the recent ramp up in aggression has been at the direction of President Xi who, in his formative years as a party apparatchik, was impressed by how the war with Vietnam in 1979 was used to consolidate power in the politburo.  President Xi has accumulated more power than any Chinese leader since Deng Xiaoping. He is using an anti-corruption campaign to purge political opponents.  Chinese leaders are supposed to only rule for ten years before standing aside.  Just two years into his presidency, Xi’s supporters have raised the possibility of resurrecting the position of chairman of the party (abolished by Deng to stop another Mao) so that Xi could continue to rule from that position.  President Xi is a nasty piece of work who has been toughened up by his life experiences.  At the age of 15, he was sent to live and work with peasants in the yellow earth country after his father was purged.  His accommodation was a cave.  His stepsister suicided due to his father’s oppression by the Red Guards.
Japan
Japan sees this war being thrust upon it and is approaching it with a great deal of foreboding.  It sees it as being inevitable, though Prime Minister Abe did ask to meet President Xi in Indonesia recently.  President Xi intends to kill many tens of thousands of Prime Minister Abe’s countrymen, so the meeting was strained.  Yesterday, Prime Minister Abe addressed a joint session of the US Congress, part of his making the rounds to make sure everyone is on the same page with respect to absorbing and repelling the Chinese attack.
United States
The United States believes that a rules-based wold order needs to be maintained for global security and prosperity, including its own prosperity, because that relies upon world trade to a large extent.  So for the United States, this war will be about preserving access to the global commons.  The US military establishment has not kept the public up to date with all of China’s preparations for war, probably because they do not want to be perceived to be causing escalation.  But the US military is in no doubt that China will start a war.  The main unknown is the timing.
Chinese aggression has been a godsend to the US Navy, which had lacked a credible threat and had faced ongoing shrinkage.  There is a tendency to overstate the efficacy of enemy weapons systems.  The Chinese would have read the US Navy reports on their weapons systems, which would have emboldened them further.
How The War Will Be Conducted
There will be two main theatres of operation: the East China Sea north of Taiwan and the South China Sea west of the Philippines.
China claims sovereignty over the Senkaku Islands (last occupied by the Japanese about 100 years ago) and the entire Ryuku chain from the Yaeyama Islands at the southern end to Okinawa in the north.  If it is going to seize the Senkaku Islands, it might as well seize the Yaeyama Islands at the same time.  To that end, China is building up a military base in the Nanji Islands about 300 km west of the Senkakus.  This includes a 10-pad helicopter refuelling base which suggests that the initial assault will be led by helicopters overflying Japan’s coast guard vessels around the Senkakus.
China has a substantial fishing vessel fleet and merchant shipping totalling 70 million tons.  It has been using its fishing fleet to harass the Japanese coast guard around the Senkakus and as far east as the Osagawa Islands, which includes Iwo Jima.  This suggests that fishing vessels could be used to land Chinese Special Forces to widely attack Japanese bases that would normally be considered to be well back from the front line.  These forces would be used sacrificially to cause maximum mayhem to dispirit the Japanese defense.  In the north, the Chinese approach would be to seize and hold against the Japanese and US counter attack.
In the South China Sea, China is building seven massive forts and one airstrip.  The forts are designed with flak towers standing out from the corners so that each tower has at least a 270° field of fire.  The forts seem to be designed to take a large amount of punishment and hold out until they can be relieved.  China wins if it is still in the possession of these forts by the end of the war.
China is likely to start the war in the south with attacks on other countries’ bases in the Spratly Islands and US bases in the region, as far east as Guam.  A long war will be bad for China in that the run down to the Spratly Islands from Hainan Island is very exposed, both for ships and aircraft.  Vietnam has been upgrading its radars and one hopes all the non-Chinese combatants will be sharing targeting information.  US AWACS over the Philippines will be able to track Chinese targets handed over from Vietnam.  Singapore is likely to operate its F-15s out of Cam Ranh Bay.  Chinese aircraft that survive the run down will be at the end of their range by the time they get to the Spratly Islands. 
The US Marines have taken up a number of bases in the Philippines with the intention of mounting the attack that will remove the Chinese from their newly constructed forts.  A number of US weapons systems, such as the USS Zumwalt, may have to be rushed into service to that end. 
In the bigger picture, Japan and China will try to blockade each other, mostly with their submarine forces.  Japan’s navy has a qualitative edge over China and is most likely to win the blockade battle. 
Industry throughout Asia will be badly affected by the war, but Chinese industry in particular is likely to grind to a halt quickly, and this will eventually cause social disruption.  The longer the war goes on, the worse China’s relative position becomes.  Meat will disappear from the Chinese diet.  Unsold soybeans will pile up in US warehouses. 
The removal of the Chinese bases in the Spratly Islands will allow a peace settlement with whoever ends up running China.  It will be one of the most pointless, stupid and destructive wars in history, but that is what is coming.
David Archibald, a visiting fellow at the Institute of World Politics in Washington, D.C., is the author of Twilight of Abundance (Regnery, 2014)