Singapore’s Union of Security Employees (USE) said on Thursday that it “stands firmly behind” the security guards involved in a confrontation with a Hong Kong school principal in which he swore at them.The secondary school principal, Lee Cheuk‑hing, who was on a trip to Singapore with a group of students, was seen arguing with the guards over a parking matter at SAFRA Jurong, a recreational club, in a video widely circulated on social media.Lee has since tendered his resignation from San Wui...