As time passes, we lose more of our World War II veterans, a reminder of how important it is to preserve history.

We were saddened at the loss of a great hero, 99-year-old Victor Chang, a WWII veteran who flew a US fighter jet over the Hump Route along the borders between China and Burma as one of the Flying Tigers. He died on Christmas Day at the Sonoma Healthcare Center.

Chang was among the pioneers of the American Volunteer Group (AVG). In one of the interviews with the Chinese media in August, he explained why he decided to join the Flying Tigers and go to China in 1939.

"I'm Chinese," Chang, paralyzed in his wheelchair, mumbled several times. Chang flew P-40 and P-51 fighter jets during his seven years of service in China, shooting down two Japanese planes and destroying many enemy planes on the ground, along with transporting wartime supplies.

Asian-American communities are racing against time to preserve historical materials about the teamwork between China and the US during World War II and publicizing the friendship between the two nations that fought the Japanese invaders since 1937, ending with Japan's defeat in 1945.

The task of preserving the historical truth of WWII is especially important as the Japanese government and politicians attempt to revise Japan's record of wartime aggression and atrocities against their Asian neighbors 70 years ago.

The preservation efforts include collecting the historical documents, artifacts and oral histories of WWII veterans. There will be two large-scale exhibitions between coasts on the Flying Tigers in the United States, co-sponsored by the Chinese government and the Flying Tigers Foundation.

Japan invaded northeast China in September 1931, while historians view July 7, 1937, as the start of the Sino-Japanese War. On that day, after long planning, the Japanese Imperial Army opened fire on Chinese soldiers stationed in Wanping Town, a crucial access point southwest of Beijing, and launched a full-scale invasion of China.

According to 89 Japanese wartime documents made public on April 25 in Jilin province, Japanese troops committed shocking atrocities in China - they abducted and trafficked Chinese women and forced them into sexual slavery at "comfort stations"; they occupied the city of Nanjing and killed more than 300,000 Chinese civilians, burning down a third of the houses in the city and raping more than 20,000 women, including teenagers; and they carried out bacterial experiments on people at Unit 731, the notorious top-secret biological and chemical warfare research base established in Harbin in 1935, which served as the nerve center for Japan's biological warfare campaign in China and Southeast Asia during WWII.

Japan also cut off the wartime supply lines of the Chinese Army in the northeast and southeast. The last transit line along the Burma Road, although severely bombed by Japanese invaders, had opened to traffic in August 1938 to transport strategic international donations and supplies.

In order to guarantee a smooth operation of this only route, US President Franklin D. Roosevelt in 1941 authorized the creation of a clandestine "Special Air Unit", which consisted of three combat groups equipped with US aircraft and staffed by pilots and technicians recruited from the US military to help China.

Better known as the American Volunteer Group, its members joined their Chinese counterparts in the fight against the Japanese.

On Aug 15, then-Chinese Consul General Yuan Nansheng paid tribute to four WWII veterans in the Bay Area, including Chang; Robert Hong, 90; William Behrns, 94; and 101-year-old Moon Fun Chin.

Yuan praised the veterans' heroic deeds and contributions to the ultimate victory in 1945 in China's War of Resistance against Japanese aggression, and stressed that the victory and postwar order must always be upheld.

Calling the veterans "priceless treasures of humankind and living testimony of the US-China friendship", Yuan said historians and the Asian-American community need to make greater efforts to preserve the history of the Flying Tigers.

In Beijing in July, in commemorating the 69th anniversary on the victory against Japanese aggression, Chinese President Xi Jinping said: "We will never forget the American Flying Tigers who fought shoulder to shoulder with the Chinese military, and opened up, at the risk of their lives, the Hump Route to deliver strategic suppliers to China."

In a speech on Dec 13 marking the country's first national ceremony commemorating the Nanjing Massacre, Xi said that history will not be altered as time changes, and that facts will not disappear because of denials.

Contact the writer at junechang@chinadailyusa.com