Because science is defined as a method, it follows that what makes or breaks science is not the subject at hand, and not even the proposed thesis, but the process followed to produce such thesis. Scientific statements are products of science, but they're not science themselves. This means that they're always open to eventual improvement, refinements or even refutations, and no amount of evidence in favor of a thesis can ever shield it from attempts at falsification.
Instead, in state pseudoscience, whenever the scientific method seems to lead to a certain conclusion "X", then "science" ceases being a method and becomes identified with X itself; the consequence of this is that any attempt to question X is taken as an attempt to question "science" itself, with the inevitable result that X becomes set in stone as an unquestionable dogma, violating one of the main principles of the scientific method, which is falsification.
