Trump's irrational travel ban is an exercise in extremism

To borrow a famous phrase from another American president, no one should ever misunderestimate the capacity for idiocy of Donald J Trump.

- SEAN O'GRADY

You'd think we'd be used to it by now - but today we're coming to terms with another Trump travel ban, the embarrassment of which has been amplified by his decision to announce it in a solemn national address on the television; like JFK in the Cuban missile crisis, or Nixon saying he had never been a quitter in his resignation statement.

Restricting travel to the US from 19 countries with "hostile attitudes" or a "significant terrorist presence" is Trump effectively saying "we don't want them here" - "them" being, with few exceptions, people from Afghanistan, Myanmar, Chad, Republic of the Congo, Equatorial Guinea, Eritrea, Haiti, Iran, Libya, Somalia, Sudan and Yemen, all of whom will be "fully" restricted.

Scarcely more welcome are the nationals of Burundi, Cuba, Laos, Sierra Leone, Togo, Turkmenistan and Venezuela, who will be partially restricted. Trump says these countries don't vet their people as well as they should, which may well be true, but most dedicated terrorists will always find a way to deceive their own and any other government they encounter.