In criticising Trump’s abrupt withdrawal from Syria, Janine di Giovanni won’t admit that what passed for American policy – and by default that of the west – never made sense (Trump’s Syria withdrawal has handed a huge gift to Isis, 22 December). Assad’s secular regime did not pose a threat to the west. Yet from the start of Syria’s troubles we diplomatically sided with the insurgents. We trained “moderates” and supplied them with “non-lethal” equipment. When it became obvious that Saudi Arabia, Qatar and Turkey were aiding Islamic State, we turned a blind eye.

Then there was Washington’s creation of the Kurdish-led Syrian Democratic Forces. It was in a sense too successful, occupying much of north-east Syria. No thought was given to reconciling Kurdish rule over extensive Arab-populated areas. And Washington must have known that Turkey would never tolerate a bordering Kurdish state. Syria’s Kurds would have been better off aligning themselves with Assad.

Yugo Kovach

Winterborne Houghton, Dorset

• Trump’s ordering the withdrawal of US troops from Syria, in the very week that Recep Tayyip Erdoğan, Turkey’s president, has declared his intent to attack the enclave of Rojava, is a shocking betrayal of the Kurds, until now armed and supported by the US, who have been successfully fighting Isis in Syrian towns and villages throughout this conflict.

The Kurds, in Syria and Turkey, and their long-imprisoned leader, Abdullah Öcalan, must be key participants in any peace process. Now, more than ever, they require the immediate support of the international community to protect them from annihilation.

The UK, the main provider of arms to Erdoğan, must stop appeasing Turkey and selling it arms – and must use all its diplomatic clout to get Trump to cancel this order. Isis is not defeated and we must not yet again betray the Kurds, a people committed to peace and democracy.

Margaret Owen

London

• Turkey has said it will invade and destroy the quasi-independent Kurdish enclave of Rojava in northern Syria: the Kurds “will be buried in their ditches”, Turkish leaders have said. Surely the world cannot just stand by and watch this happen?

Brendan O’Brien

London

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