The US seems to never tire of accusing China of espionage and spying. On Wednesday, a US district court sentenced Su Bin, a Chinese businessman, to 46 months in prison and handed him a $10,000 fine after he admitted conspiring with two Chinese military hackers and hacking US defense contractors from 2008 to 2014 to steal data, including information on Boeing C-17 strategic transport aircraft and F-22 and F-35 fighter jets.

What's noteworthy is that Su said he helped the hackers for personal financial gain, according to prosecutors. The case appears to be more like the economic espionage that is often seen between competitors in many parts of the world.

But again, the US sophisticatedly portrayed itself as a victim of military espionage, though it is more often a predator itself. The US tries hard to connect Su's case with the Chinese military and paint it as government-backed hacking and spying.

"The Cold War is not over, it has merely moved into a new arena: the global marketplace." That's what the FBI states on its website. A worrying tendency in the US, and to an extent Canada, is that Chinese are increasingly the subjects of witchhunts. From Chinese-American professors to staff at Chinese companies, they are ever more likely to be targeted by US law enforcement agencies over suspected espionage. Each case is accompanied by media and politicians hyping up "China Threat" theory.

Last year, the US Justice Department accused Chinese-American scientist Xi Xiaoxing of providing Chinese scientists with advanced US technology. But it turned out Xi's collaboration with his Chinese counterparts didn't have economic value and did not involve proprietary material, and the department finally dropped the case. Also last year, Sherry Chen, a Chinese-American hydrologist, was still fired even though she was cleared of being a spy.

The victims cannot ever repair their reputations, and the American authorities have never tried to help them do so, reinforcing the biased impression that many Chinese are spies. The US has to drop its Cold-War mentality and look at China in a fair manner. When frictions in economic activities take place, both sides had better exercise restraint and figure things out. The last thing that the China-US relationship needs is pointing fingers at the other with groundless accusations.