The symbolism is on top of the "warmongering on allies" rhetoric, that could, in this case, push for a war on Mexico or takeover of its territorial rights to oil extraction in the Gulf. The lust over Greenland is its strategic role in attacking/defending Europe. The resources there are very expensive to extract due to infrastructure needs. The Panama canal is to stop Chinese trade/influence, but usual US policy is threats/coups instead of offering market prices. Panama canal fees are high due to droughts related to global warming which Trump wants to increase beyond reparability.