You are not going to get any credible explanation from the Chinese.
Yes...Solid fuel is preferable for weapons. But why ?
Liquid fuel burns hotter and can be throttled -- meaning controlled like how you can 'rev' up/down your car's engine by stepping on the gas pedal. But the trade-off is that liquid fuel requires much more maintenance, such as temperature controls which is the most intensive.
So why does space exploration vehicles uses liquid fuel but weapons uses solid fuel ? After all, are they not rockets at the core ?
The difference is that weapons have to be on stand-by status for looooooong periods of time while space exploration vehicles are used pretty much immediately. The Space Shuttle uses liquid fuel and its large main tank is filled when there is a flight scheduled. For missiles, there is no war scheduled but since there is always the potential of a war, no matter how remote, the missiles must be readied and solid fuel offers the best solution. This is from air-air missiles to ICBMs. The disadvantages for solid fuel are that it is not as powerful as liquid fuel and cannot be controlled. Once ignited, the fuel must burn to depletion.
