President Trump’s decision to green-light Turkey’s invasion of northern Syria (‘Betrayal is a bitter taste.’ Kurds’ anger at Trump as bombs fall, 11 October) is yet more proof of the danger he poses to security in the Middle East. His callous betrayal of the Kurdish people is both reckless and dangerous. The Kurdish-led Syrian Democratic Forces have been key allies in bringing peace and stability to the region and countering the threat of Isis. By allowing Turkey to invade, President Trump has risked destroying everything that has been achieved, and allowing the possible escape of thousands of Isis prisoners.

President Erdoğan has shown flagrant disregard for international law and civilian life, and has ruthlessly persecuted trade unionists, journalists and political opponents at home. We cannot sit by while Turkey launches a brutal attack on Kurdish communities. UN reports show that 70,000 people have already been displaced.

The UK government – in partnership with our international allies – must immediately call for a no-fly zone, exert the maximum pressure on Erdoğan, and hold Trump accountable too. Trump’s behaviour on Syria should be a cautionary tale. This is not a man we can trust and depend on.

Frances O’Grady

TUC general secretary

• America’s recent betrayal of the Kurds is not a unique action; it happened before, in 1975. When Richard Nixon visited the Shah of Iran in May 1972, the Shah encouraged Nixon to support Mustafa Barzani, leader of a Kurdish revolt against the Ba’athist regime in Iraq. On 18 July 1972, the director of central intelligence, Richard Helms, stated in a memorandum that made it all the way to the president that assistance to the Kurds’ campaign against the Iraqi regime would keep the Ba’athists “off balance”. On 9 April 1972, Iraq had signed a treaty of friendship and cooperation with the Soviet Union. Thus, assistance to the Kurds would preoccupy both the Iraqis and the Soviets, and hence reduce opportunities for them to take actions against Iraq’s neighbours.

Soon Barzani’s organisation was receiving Iranian military support, and large-scale US financial and weapons assistance. During 1974-75, the Kurdish insurgency resulted in over 60,000 casualties. So intense had the conflict become that an Iran-Iraq war was seen as possible. However, at a 1975 OPEC meeting, Iran and Iraq reached an agreement, settling certain differences, including Iranian support for the Kurds. As Iraq-Iran tension evaporated (for now), Iranian support for the Kurds stopped. As a result, US support for the Kurds stopped immediately. The Iraqi regime soon crushed the Kurdish insurgency.

When Henry Kissinger was asked at a 1975 congressional hearing why aid to the Kurds had been cut so abruptly, he replied: “Covert action should not be confused with missionary work.”

Trump’s use of words may not match Kissinger’s turn of phrase, but for the Kurds the result is the same. The US will use them when such a policy is expedient, and cast them off when they are no longer of use.

Ken Webb

Epping, New South Wales, Australia

• The sense of betrayal expressed so eloquently by the elderly Kurd Hussein Rammo in your article is both macabre and ironic. The Kurds were promised an autonomous Kurdistan by the treaty of Sèvres in 1920, only for this to be rescinded and for the Kurds to end up scattered between Turkey, Iraq and Syria by the treaty of Lausanne in 1923.

DBC Reed

Northampton

• A very important feature of the “safe zone” that Turkey is seeking to create in north-east Syria is that it comprises practically all the rain-fed agricultural land in that region. There is a rolling plain across north-east Syria, north-west Iraq and a narrow strip of south-east Turkey. North of that zone are the Taurus mountains; and south of that narrow east-west band there is semi-desert, which rapidly shades into arid desert. The band of green land that can support rain-fed agriculture is where population (predominantly Kurdish) is concentrated. Turkish government statements call the Kurds terrorists and claim that they, along with Isis, threaten Turkey’s frontier.

The Turkish military invasion of Syria appears to be intended to push the indigenous population out of the habitable zone into the semi-desert that simply cannot support them. Removing the “terrorists”, according to the Turkish government, will enable them to settle the region with some of the huge number of Syrian refugees who fled into Turkey, predominantly from west Syria. Who is going to cope with the humanitarian crisis when a large population is driven from their homes into the semi-desert? How will UN and NGO aid be able to reach them? And who will be able to feed and support the Syrian refugee families who are scheduled to be dumped in the north-east Syrian “safe zone”, once the Turkish military has bombed and shelled the infrastructure to ruins?

Trevor Watkins

North Queensferry, Fife

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