Dave is a terrorist, and should be locked up forthwith.
You'll like this....the Terrorism Act 2000 defines a terrorist as:
1 Terrorism: interpretation.
(1) In this Act “terrorism” means the use or threat of action where—
(a) the action falls within subsection (2),
(b) the use or threat is designed to influence the government [F1or an international governmental organisation]F1 or to intimidate the public or a section of the public, and
(c) the use or threat is made for the purpose of advancing a political, religious [F2, racial]F2 or ideological cause.
(2) Action falls within this subsection if it—
(a) involves serious violence against a person,
(b) involves serious damage to property,
(c) endangers a person’s life, other than that of the person committing the action,
(d) creates a serious risk to the health or safety of the public or a section of the public, or
(e) is designed seriously to interfere with or seriously to disrupt an electronic system.
So Dave is a terrorist by all 3 definitions in section 1; and 3 out of 5 of the section 2 definitions.