Maybe you should look up its definition because that's not what invasive species means. They aren't called invasive species when they have arrived on their own

Maybe you should look up its definition because that's not what invasive species means. They aren't called invasive species when they have arrived on their own without human intervention and then outcompete. Japanese Knotweed did not come to Europe and US by its own accord, it was intentionally planted in gardens from where it escaped and is now causing ecological and economical damage at a massive scale. Calling it an invasive species is basically admitting that it was a mistake in introducing it to another environment, and also (sometimes legally) forbidding of adding any more and/or mandating destroying existing ones.