Obstinacy

[Zipporah Schumaker]

A fixedness in will, opinion, or resolution that can not
be shaken at all, or only with great difficulty; firm and usually
unreasonable adherence to an opinion, purpose, or system; unyielding
disposition; stubborness; pertinacity; persistency; contumacy.

[Donald Trump]

the quality of being unreasonably determined, especially to act in a particular way and not to change at all, despite what anyone else says: