Wanting to correct public health and/or environmental problems caused by invasive species doesn't mean 'blaming' them.  They're animals.  Not subject to blame.  I no more blame cats than the St. Paul tribal council blames rats that attack their native ground-nesting seabird rookeries.  But they do kill the rats, and require vessels tying up at their port to have rat-guards on their lines to keep more from coming ashore.

And the reason feral Europeans aren't invasive 'species' is because they're the same species as those they colonized, and they got there on their own.  All humans are a 'weed' species--we're capable of taking advantage of even sudden favorable changes in our environment to rapidly increase our numbers and expand our range.  Frequently 'weed' species benefit from human-engendered environmental changes.  Example, clearing forests and planting grains increase rodent populations, and in turn attract and increase venomous snake populations, like fer-de-lance, around farms.