Terrorism is actually a pretty simple but specific definition. Terrorists use unlawful violence and threats of violence to influence the government or an international governmental organisation, or to intimidate the public. They do this in pursuit of a political, religious, racial or ideological cause.

It doesn’t take much money or many resources to engage in violence or even make threats. Certainly having money and resources at your disposal make you more effective but it’s a rather low but still specific bar to cross to be considered a terrorist.