As tensions between Taiwan and China continue to escalate, satellite images reportedly show amphibious armoured vehicles and mobile missile launchers massing at military bases near the island nation.

Though Taiwan, a country of 25 million people, is happy as an independent democracy, Beijing insists it is a "breakaway province" and "inviolate" Chinese territory, repeatedly stating it will use force to bring the island back under China's control.

Now the images have shown the People's Liberation Army (PLA) moving the military vehicles into the Eastern Theatre Command on China's coastal cities across the strait from Taiwan, with missile launchers well within range to hit any targets in Taiwan.

"We make no promise to abandon the use of force, and retain the option of taking all necessary measures," Chinese leader Xi Jinping said in a recent speech.

Under its 'one country, two systems' policy, Beijing insists Taiwan is part of its sovereign mandate. Which is why its so-called 'wolf warrior' diplomats have reacted with outrage at news this week that the US Health Secretary will visit the island to discuss its success in combating the COVID-19 pandemic.

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Meanwhile, Chinese fighters and bombers have been engaged in a series of "combat readiness" exercises over the disputed South China Sea, with combat aircraft and naval vessels observed visiting illegal island fortresses in the Spratly Islands

Tension reaching boiling point

The Type 05 amphibious armoured vehicles are designed to deliver troops from the sea across a beachhead battlefield.

"The PLA are also deploying the powerful Type PCL191 multiple launch rocket systems to the ground forces of the Eastern Theatre Command," Kanwa Asian magazine defence editor Andrei Chang writes. These have a range of some 350km.

"The risk of a military clash exists, and we should be alert to it," Beijing Institute of International Relations Professor Li Haidong said

"The Taiwan Strait is just 180km across. The PCL191 rocket launchers are able to destroy all military bases and government buildings on the island accurately."

Meanwhile, Taiwan has responded by sending a company of about 200 marines to reinforce the Pratas Islands national marine park in the South China Sea – 445km from Taiwan and 300km from China.

"The marines left for the Pratas about a week ago and will remain there on a short-term rather than a long-term basis," a military source told the South China Morning Post.

US gets involved

The increase in Chinese military activity has also been met with a response by the United States. Its surveillance aircraft have stepped up the extent and frequency of their activity in and around Taiwan, closely monitoring Beijing's forces. Bomber movements are being observed. Submarines are being tracked. Activity on and around island fortresses are being watched.

A Chinese State University think-tank reports 67 US reconnaissance aircraft had been detected in the area in July. This was almost twice that seen in previous months.

"The risk of a military clash exists, and we should be alert to it," Beijing Institute of International Relations Professor Li Haidong said.

"There is a high possibility that the US will further escalate its conflict with China before the election, Professor Li said, noting that US Secretary of State Mike Pompeo's call for the 'free world' to unite against China implies that once the US launches military action against China, many countries will stand with it."

Spratly surge

This week, Chinese state media has lauded a 10-hour flight by six of its Su-30MKK fighter jets from the mainland to Subi Reef in the Spratly Islands.

There they joined two Chinese navy warships, a Type 054A frigate and a Type 056 corvette. These were photographed anchored in Mischief Reef's protected lagoon.

The reef, unilaterally occupied by Beijing before being transformed into an artificial island fortress, is one of the largest features of the Spratly Islands judged by the UN to fall far outside Chinese territorial control.

Touted as an air-sea rescue facility, it features a military-grade 3km runway, armoured hangars, communications arrays, radars and weapons towers.

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Philippines President Rodrigo Duterte has all but surrendered his nation's claim to the traditional fishing grounds, saying last week: "China is claiming it, we are claiming it. China has the arms, we do not have it. So, it's simple as that. They are in possession of the property. So what can we do? We have to go to war. And I cannot afford it. Maybe some other president can. But I cannot."

Military analysts have noted that the 10-hour flight by the Chinese fighters to Subi Reef was unnecessary. At its cruising speed, the Su-30 needs only three hours to cover the distance as they can fly at speeds of up to 2100km/h, with a horizontal flying speed of 1400km/h.

"The math on a 10-hour trip doesn't make sense," China Aerospace Studies Institute director Brendan Mulvaney told Radio Free Asia.

"It's about 2100km from Changsha (south-central China) to the Spratlys, which should only take two to three hours at typical cruise speeds. At 10 hours round trip, that implies they're flying at 420km/h which is unlikely".

Its duration, however, may be intended as a signal that its pilots are training for the endurance necessary to strike more distant facilities, such as US bases in Guam, Singapore and Darwin.

The Chinese Communist Party (CCP)-controlled Global Times declared the exercise to be of "significant strategic value to the PLA's complete patrol coverage of the entire South China Sea".

Invasion fears

The latest moves are just the most recent examples of intensifying Chinese military activity around Taiwan.

"As China is eager to expand its communist ideology and authoritarian international order, Taiwan is on the frontline of defending freedom and democracy," Taiwan's Foreign Minister Joseph Wu said last week. "What China is doing now is continuing to ramp up preparedness to solve the Taiwan issue. The threat is on the rise."

The odds are against the island nation, with Chinese military performing "simulated invasions" and daily incursions by combat aircraft.

Taiwan has 140,000 troops. China has 1 million. Taipei has 350 fighters. Beijing has 1500.

And Xi may have painted himself into a corner.

But the battleground has now reformed between Beijing and Washington as US-China relations deteriorate.

Beijing declares any international engagement with Taiwan crosses a "red line". Washington insists it will act to preserve Taiwan's democratic values.

It's a scenario that could lead to "some kind of a military dust-up", Asia Society Centre on US-China Relations analyst Orville Schell told CNBC.

And Beijing's options are rapidly narrowing

"Everything else having failed, President Xi may therefore feel compelled to put a premium on a military strategy in the Taiwan Strait," said Michael Cole from the Global Taiwan Institute. "The two pillars of Beijing's strategy towards Taiwan – coercion and incentivisation – have failed to arrest ongoing trends in Taiwan supporting independence and a democratic form of governance."

And Xi may have painted himself into a corner.

He's been whipping up nationalist fervour in an attempt to distract his people from growing economic and civil challenges. He's proclaimed to his party colleagues that the "embarrassment" of Taiwan cannot be passed from "generation to generation".

Taiwan has become bolder in standing up to China after observing the CCP's behaviour in asserting control over Hong Kong.

"Taiwan may be small, but we know what we are fighting for is more than Taiwan," Wu said. "It's our values that are at stake."