If the US wants to have surveillance for those cranes, can't they just stick their own surveillance equipment on those cranes ?
>The US is paranoid, but also kinda should be…
In that case I don't get it. From a technical point of view the most secure crane, is the one that uses technical minimalism. If you only implement the technology needed to operate the crane, the attack surface for subverting it's function is the smallest. If you add more features like surveillance, that massively increases the attack surface.
As far as container security goes, i would try to figure out ways to scan their contents for malicious stuff. The scan method has to be fast and economical, so x-ray-ing a bazillion containers is out. However you can scan for particulate emissions to find hazardous materials like toxic chemicals or explosives. You only need an air-pump and a molecular-particle detector to extract a container-gas-sample, which only adds a few seconds to container processing because it only requires sticking in a small suction-tube in one of the many container-drain-holes. That method is neigh impossible to beat because it will detect particles even through many layers of plastic wrap. Inherent Molecular vibration means all containers leak a little. A few molecules will always manage to wiggle through the walls of any container, and even low cost mol-dedectors are ridiculously sensitive.
>the American public should be more paranoid about the American state itself.
Even if you trust your own government, you have to be aware that all technical backdoors are very promiscuous.
In a potential cyber-war between the US and China, the Chinese will have access to all those backdoors as well. Backdoors have become near-infinite-value targets, and any rational actor with the means to pay the price for getting in, will do so. This isn't just my opinion, this is what most technical security researches think.