The arguments can be the same but have entirely different hidden variables that make it fine to use the argument in one context and not the other.

Also, this ignores that the government works for citizens, no matter their race. Promoting racial equality among citizens is a function that the government might undertake. Pursuing policies that favor citizens over non-citizens falls in line with that same reasoning.

No it's really not the same because we have laws against racial discrimination, but it is the entire purpose of the state to represent the interests of its citizens above all others.