Forty-five years ago when Chinese and Japanese leaders signed the Treaty of Peace and Friendship between Japan and the People's Republic of China, they wanted the neighbors to develop a close bond, so the two peoples would live in lasting peace and harmony.

In the decades that followed, the two sides managed to foster a generally stable and constructive relationship, which not only nurtured good feelings between the two peoples but also significantly boosted both their economies.

Historical and territorial issues did interrupt bilateral activities once in a while. But politicians in both Beijing and Tokyo demonstrated reason and statesmanship to prevent them from derailing the overall relationship. From a purely utilitarian perspective, both sides knew their economic importance to each other. They knew the cost of China and Japan turning against each other, too.

As the historic treaty celebrates its 45th anniversary, however, the kind of lasting friendship and harmony it envisioned appears fragile and illusive.

In conspicuous contrast to the past, leaders of the two countries have not met or talked officially for a long time, and high-level government-to-government exchanges have been rare in the recent past. Perhaps most unsettling of all, multiple polls have shown a dramatic drain in friendly feelings between the two peoples.

Unlike in the past when Beijing and Tokyo would go to great lengths to mend fences whenever relations hit a snag, China-Japan relations are apparently facing their own climate change. This may have originated from increasingly negative mutual perceptions and subsequent growth of distrust, and acerbated by Tokyo's strategic anxiety over Beijing's alleged behavioral change toward greater aggressiveness and strategic goals.

What annoys Beijing the most, however, is Tokyo's proactive role in its technology and security alliance with the United States to target China. While the US-led West openly designates China as a threat, Japan's choice has obviously been a disservice to that 45-year-old oath of friendship.

That's why when he exchanged congratulatory messages with Japanese Prime Minister Fumio Kishida on the 45th anniversary of the treaty on Monday, Premier Li Qiang called for reliving the spirit of the treaty, which Kishida said was the bedrock of a relationship characterized by lasting peace and friendship.

That's also why Foreign Minister Wang Yi said the two countries should take advantage of the 45th anniversary "to remember the original intention of the treaty ... and bring China-Japan relations back to the track of sound development".

China and Japan should oppose ideological confrontation and reject a new Cold War, Wang said. Instead, they should develop a close bond, as the treaty says, based on mutual respect and mutual benefit.