Iran is pushing the Houthis to prepare for a renewed campaign against Red Sea shipping, contingent upon any further escalation by the US in its war on the Islamic Republic, according to European officials familiar with the matter.Leaders of the Yemen-based Houthis, a militant group backed by Iran, are weighing options for more aggressive action after launching ballistic missiles at Israel, the people said, asking not to be named discussing sensitive matters.There are divisions within the...