Apparently its political

I've now been told that getting a lab job is political, that they will only take those who have either done it before, or those who they think will be around for a long time. In other words, international students need not apply because a) we , in their minds, haven't done it before, and b) won't be here long (although we seem to stick around longer then their students because we actually finish our PhDs). So they claim there is nothing wrong with what they are doing.