Would the same apply for someone who physically took something essential to national security hostage and then demanded money?
Would that change if they, for example, demanded the release of prisoners of a specific political persuasion?
Would that change if they, for example, demanded the release of prisoners of a specific political persuasion?
How would that not be classified as a political motive?
Yes.
"Terrorism is, in the broadest sense, the use of intentional violence to achieve political aims." https://en.wikipedia.org/wiki/Terrorism