Australia and New Zealand have implemented large invasive species control programs with Predator Free New Zealand and Australia’s pledge to kill 2 million cats by 2020. These programs have received heavy criticism, particularly from invasive species sceptics based in the USA and Europe. I aim to clarify and address the strongest argument that has emerged in the recent literature. Invasive species sceptics argue that the control of invasive species is a form of xenophobia, there is no sound reason to control invasive species or even prefer native species over non-natives. Preferences for natives are just prejudice, a prejudice not always held by the layperson. The public often shows affection to our alien compatriots; for example, the public support for Brumbies in Snowy Mountains, or the wish to preserve deer in New Zealand to maintain deer hunting. Critics of invasion biology have argued that invasive species do not destroy ecosystems but instead create “novel ecosystems”. These novel ecosystems are claimed to be more biodiverse than extant ecosystems and across the globe most local ecosystem patches have increased in biodiversity! These more biodiverse ecosystems will provide more ecosystem services than extant ecosystems and, therefore, are more valuable. This position is only possible with the following assumptions about how we justify conservation. First, public interest or opinion should determine our stance towards the control of species. Second, the direct monetary value of ecosystem services is the only justification for conservation past public interest. Third, biodiversity can be flexibly defined. Four, the analogy with xenophobia in human migration is sufficient to reject invasion science. I reject all these assumptions. Once we see that there is more to conservation then opinion and immediate monetary gains, we can see that such slippery stances defending invasive species are not justified