Rivalry between China and the US has to be carefully managed to prevent relations from nosediving. Incidents have too often in the past turned buoyant ties sour. Such could easily be the case with the confrontation between five Chinese ships and a US navy vessel off Hainan Island on Sunday. Accusations and demands for an apology are being carelessly hurled about, and cool heads are needed to prevent an escalation. The incident is worryingly reminiscent of the collision between a Chinese jet fighter and a US military surveillance plane over the South China Sea near Hainan almost eight years ago. As now, it came in the dawning weeks of a new American presidency. Tit-for-tat claims were instant and a diplomatic storm quickly ensued. Relations frosted over and the thaw was not apparent until the latter half of George W. Bush's second term as president. We have cause for hope. There are marked differences between that incident and the present one. The pilot of the Chinese plane was killed in the collision and the American crew was subsequently detained on the island for 11 days. Diplomacy saved the day, but the damage had been done. It is unclear this time, just as then, who is at fault. Beijing claims the US vessel, the USNS Impeccable, was on a spying mission and in its territorial waters. This was justification for the flotilla of craft to surround it and try to escort it away, officials said yesterday. The Pentagon does not deny that the ship was towing surveillance equipment designed to check on submarines berthed at Hainan, but contends it was in international waters. There is no doubting the diplomatic war of words that has resulted, though. A Foreign Ministry official said that Chinese and international law had been violated. China's actions were denounced by a Pentagon spokesman as 'reckless, dangerous and unprofessional'. Neither side is budging; there is a danger that the sound footing to relations established during US Secretary of State Hillary Rodham Clinton's visit to Beijing last month will be torn asunder. Nations the world over spy on one another for commercial, diplomatic and military advantage. This is especially true for China and the US, which have much to gain from having the upper hand. But the golden rule of espionage is not to get caught. On Sunday, the US was caught red-handed. Moderation is urgently needed. China and the US must work together, not against one another. US President Barack Obama has pledged the right diplomatic approach. Promising Sino-US ties cannot be allowed to be squandered.