Chinese citizens have so far complied with whatever the CCP has imposed. Any unrest is typically fairly marginal and swiftly put down. Tiananmen left almost no lasting impression domestically and has virtually been forgotten. With unbridled nationalism thrown into the mix, I don't see it as unlikely that Chinese citizens would go along with a war. Even if they're not too keen, so what? The US has recently fought wars many Americans weren't too keen on. China could quite easily demand more sacrifice than that from its citizens, and there might also be optimism as to how quickly and easily they could win, like Japan in 1942.