Preferentially treat one group of people (non-white/women/Americans) even if in the short term the revealed preference of businesses is to hire a different group of people (white/men/immigrants), such that, in the long term, the first group of people can develop the necessary skills to compete with the second group.
Short term pain for long term gain.
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.