Wars are always planned against multiple countries all the time and always have been. For example there was an operational plan for Great Britain I think that was on the books through the 1930s - War Plan Red.
https://en.wikipedia.org/wiki/United_States_color-coded_war_plans
If Weasely Clarke told me it was raining. I would get up and go look!
Your response has nothing to do with what he said.