Different cases. Chile is Mestizo majority, so non-white. Argentina is "whiter" than the US and NZ.
Chile is definitely debatable, because I found very conflicting numbers on this. According to a survey from 2011, 59% of all Chileans define themselves as "white", 25% as "mestizo" and 8% as "indigenous". Since human "races" mostly exist as a social construct, one could argue that you're white as soon as you claim you're white.
A genetic study from 1994 also stated: "At present the Chilean population is approximately 64% white and 35% Amerindian with traces of other admixture." (
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1050080/pdf/jmedgene00288-0042.pdf)