Why are so many people uptight about the word socialist?

[Ultralight]

You can be a conservative and still drive on roads.

Yes, you can be a conservative and still drive on socialist roads. But that would make one a Roads Socialist. One could identify as "Fiscally conservative, socially conservative, but roadly socialist."

It would be a fringey conservative indeed who advocated privatizing the military.

Exactly! If socialism is good for the military, why shouldn't it be good for healthcare?