Sir, – Conor Pope warns that a tax on air travel would be unfair, penalise an island nation, and that any revenue might be wasted by Government (“Is it time for a tax on air travel?” Opinion, November 4th). None of these points touches the core problem: air travel is absurdly underpriced because its environmental costs are shouldered by no one – except ultimately the planet.

Geography is no moral exemption, nor is distrust in Government an excuse for inaction.

If ticket prices rose to reflect that harm, it would not punish consumers but invite them to think twice: do we really need to fly to every match, every sun resort, every weekend abroad, just because we can? Legally, people may fly wherever they wish. But morally, in a heating world, the right to fly should be exercised with great restraint, not entitlement. To call an aviation tax unfair is to mistake inconvenience for injustice. The real unfairness lies in leaving the planet – and its poor and vulnerable majority – to pick up the tab for our cheap tickets. – Yours, etc,

PAUL O’SHEA,

Planet Before Profit CLG,

Shankill,

Dublin 18.

Sir – While the “polluter pays” principle should indicate the need for an air travel tax, providing carrots for travelling by sea and land might also be effective. Subsidies for sail and working with other countries rail networks to provide viable “rail and sail” options are needed. Rail and sail options even to our nearest neighbour, Britain, are limited. All this needs work if alternatives to flying are to become realistic options. – Yours, etc,

ROB FAIRMICHAEL,

Ballynafeigh,

Belfast.

Immigration disinformation

Sir, – Fair dues to Fintan O’Toole for giving the real facts and figures on asylum seekers and migrants (“Simon Harris is deliberately spreading disinformation on immigration”, Opini