Avira: There are deos yechidim that for goyim shituf is not assur,
I don’t think this is yehidim, I recall it goes back to tosfos, am I wrong?
> As for veterans vis a vis hakaras hatov; we don’t find a source in chazal
A related sugya on respect of zekinim in Kidushin considers whether we really respect Tal,iei Hahamim of any age, or really any old people. My rav concludes that Gemora is purposefully vague on the conclusion and both should be respected, and an elderly Aramean surely had some experiences in his life, and veteran status surely increases a chance that a person did something worthy in his life.
Generally, when you look at Gemoras re:nichrim, we probably need to look at pre-censored sources to see whether we are talking A’Z, minim, etc. Even when talking about christians, it may matter whether they are Jewish/minim, and what the current relationship with them is.
Also, none of the religious concerns would apply to free-thinkers and Muslims