Overshadowing a G7 meeting in Japan is the regional threat of China to another of its neighbours, Taiwan - Debi Edward reports
Okinawa is Japan’s southernmost prefecture; it is closer to Taipei than it is Tokyo. If conflict breaks out with China over Taiwan, the chain of 160 islands would be one of the allied forces' front lines. The southern tip of the Okinawa islands is just 70 miles from Taiwan.
It is the prospect of that war that has led to the biggest increase in Japanese defence spending since the end of World War Two.
From this year, the military budget will double, bringing it to 2% of GDP, in line with NATO nations. And much of the new resources, personnel and weapons will be placed in Okinawa.
From 1945 to 1972, Okinawa was under American control, and it is still home to 70% of US bases in Japan. Rising tensions in the region have given those bases a greater strategic importance.
Computer simulations of a Taiwan conflict show the United States could not defeat China without Japan’s support, with Okinawa as a staging point for both American and Japanese Defence Forces.
The governor, Denny Tamaki, came to power in 2018 riding on opposition to new US bases. He believes the country’s pacifist constitution is under threat.
The prime minister has gone almost as far as he can without changing Article 9 of the Japanese constitution, which outlaws war as a means to settle international disputes involving the state.
One of the most controversial elements of the new defence agreement is the acquisition of counter-strike capability.
A series of conditions would have to be met before such weapons were used, such as clear evidence that an attack had occurred or was imminent and if there was no other way to halt such an attack.
But the governor believes the prime minister has put the country on a dangerous "escalation ladder" and made Okinawa a Chinese target.
He says enhanced deterrence will have an adverse effect and disrupt the stability of the region and he fears the concentration of American bases in Okinawa means that if the country ends up in a war situation, it will be the first to be targeted.
Every year, to mark the anniversary of Okinawa's return to Japan on May 15, a peace march takes place with hundreds protesting for the removal of American troops.
For many who take part it is an emotional day reflecting on the toll past wars have taken.
More lives were lost in the 1945 Battle of Okinawa than died in Hiroshima and Nagasaki, where the US dropped atomic bombs.
A memorial on the main island has the names of 240,000 people of all nationalities who perished.
In a place where the scars of war run so deep, there is strong opposition to the government’s military build-up on the island.
We spoke to a group from the march that included 83-year-old Kiyoko Tokashiki. Aged five, she was held in a concentration camp on the island, and her uncle’s whole family was killed in the war.
She joins the peace march every year to speak out against the military build-up on Okinawa and try to make sure that war never happens again.
30-year-old Rina Matsumoto’s first trip abroad was to Taiwan - she told us she feels close to the people of Taiwan and feels sad, and afraid when she sees the news of a possible conflict.
They do what they can to campaign for peace but said the government's unprecedented military build-up shows they are not being listened to.
The Japanese self-defence force has just opened a new base on Ishigaki, Okinawa’s southernmost island closest to Taiwan, missile units have been placed there and deployed on the main island.
And more than 1,000 additional troops are to be stationed in the prefecture, most in the capital at Camp Naha.
It is a significant shift in policy and posture, one China has described as dangerous.
We were given permission to visit US base Camp Courtney and meet with Colonel Matthew Tracy the operations officer of the III Marine Expeditionary Force.
He arrived a little late for our meeting and apologised, saying things were very busy. (He wouldn’t be drawn on specifics, he just described a very "dynamic" and heightened security situation.)
He told us the US presence on Okinawa is being wrestled with at the highest level but the partnership with local Japanese defence forces is stronger than ever.
I asked him about predictions that had been made by other senior military officials regarding when China might invade Taiwan. He said it was his job to wreck such predictions and anyone making them should come out to the region, help work on deterrence and make sure we don’t get to an apocalypse.
The government in Tokyo wants Japan to shed some of its post-war military constraints and share the rising security burden in the region.
The country is also facing a threat from North Korea - it has missiles regularly landing in its waters. And Japan has a long running territorial dispute with Russia over islands to its north. That puts the country in the cross hairs of three authoritarian nations.
In Okinawa, people are looking to this week’s G7 in Hiroshima and hoping world leaders will listen to the ghosts of the past, and not let history repeat itself.
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