Tulsi Gabbard and Pete Buttigieg – the two military veterans among Democratic candidates for the 2020 nomination – clashed at the latest debate over Donald Trump’s decision to withdraw American troops from northern Syria.

Hawaii congresswoman Gabbard, who has long been a vocal critic of the US presence in Syria, said that the slaughtering of Kurds was a consequence of what she called the "regime-change war" in Syria.

She suggested that not only does Mr Trump have the blood of the Kurds on his hands, but so too do many politicians from both parties who have supported US military involvement in the region.

Ms Gabbard, who served in Iraq, said that were she to become president, she would end “draconian sanctions” on Syria that she said were killing civilians, and that she would “stop supporting terrorists like al-Qaeda who have been the ground force for the regime-change war in Syria”.

She also accused the New York Times and CNN of smearing her as a Russian asset.

Turkey launches offensive into Syria Show all 25 1 /25 Turkey launches offensive into Syria Turkey launches offensive into Syria Turkish soldiers with armored vehicles EPA Turkey launches offensive into Syria A woman flees with her children during Turkish bombardment on Syria's northeastern town of Ras al-Ain AFP/Getty Turkey launches offensive into Syria Smoke billows following Turkish bombardment on Syria's northeastern town of Ras al-Ain in the Hasakeh province along the Turkish border on October 9, 2019. - Turkey launched an assault on Kurdish forces in northern Syria with air strikes and explosions reported along the border. President Recep Tayyip Erdogan announced the start of the attack on Twitter, labelling it "Operation Peace Spring". (Photo by Delil SOULEIMAN / AFP) (Photo by DELIL SOULEIMAN/AFP via Getty Images) DELIL SOULEIMAN AFP/Getty Turkey launches offensive into Syria The first group of Turkish infantry prepare to enter Syria on the border Getty Turkey launches offensive into Syria Civilians flee AFP/Getty Turkey launches offensive into Syria Smoke billows from targets inside Syria AP Turkey launches offensive into Syria Turkish armoured vehicles enter Syria in Akcakale Getty Turkey launches offensive into Syria Civilians leave as smoke rises from Ras al-Ain AFP Turkey launches offensive into Syria A multi-rocket launcher fires in an unknown location Turkish Defence Ministry via Reuters Turkey launches offensive into Syria People wave as Turkish soldiers prepare to cross the border Getty Turkey launches offensive into Syria Girls stand together in Ras al Ain town Reuters Turkey launches offensive into Syria A woman walks as smoke billows following Turkish bombardment in Syria's northeastern town of Ras al-Ain AFP/Getty Turkey launches offensive into Syria A Turkish army's tank drives down from a truck towards the border with Syria AFP/Getty Turkey launches offensive into Syria Turkish jet taxis on tarmac after returning to a military base in southeast Diyarbakir Reuters Turkey launches offensive into Syria A Turkish armored vehicle drives down a road during a military operation in Kurdish areas of northern Syria EPA Turkey launches offensive into Syria People sit on belongings at a back of a truck as they flee Ras al Ain town Reuters Turkey launches offensive into Syria Turkey-backed Syrian opposition fighters enter Tel Abyad AFP/Getty Turkey launches offensive into Syria Civilians flee AFP/Getty Turkey launches offensive into Syria People flee Tal Abyad North Press Agency/Reuters TV Turkey launches offensive into Syria People wave as Turkish soldiers prepare to cross the border into Syria Getty Turkey launches offensive into Syria Civilians flee with their belongings AFP/Getty Turkey launches offensive into Syria Civilians flee during Turkish bombardment on Syria's northeastern town of Ras al-Ain in the Hasakeh province along the Turkish border on October 9, 2019. - Turkey launched a broad assault on Kurdish-controlled areas in northeastern Syria today, with intensive bombardment paving the way for an invasion made possible by the withdrawal of US troops. (Photo by Delil SOULEIMAN / AFP) (Photo by DELIL SOULEIMAN/AFP via Getty Images) DELIL SOULEIMAN AFP/Getty Turkey launches offensive into Syria Turkish President Recep Tayyip Erdogan, right, speaks with Defense Minister Hulusi Akar, left, as they watch the operation by Turkish forces in Kurdish areas EPA Turkey launches offensive into Syria Smoke rises from the Syrian town of Tal Abyad AFP/Getty Turkey launches offensive into Syria Turkey-backed members of Syrian National Army prepare for moving to Turkey with heavy armed vehicles EPA

She said: "Just two days ago, the New York Times put out an article saying I am a Russian asset and an Assad apologist and all these different smears. This morning a CNN commentator said on national television that I’m an asset of Russia. Completely despicable.”

Pete Buttigieg, the mayor of South Bend, Indiana, and a veteran of the war in Afghanistan, told Ms Gabbard she was “dead wrong”.

He said the “slaughter” in Syria was not a consequence of the American presence there but a result of abandoning allies. He said Mr Trump’s actions were taking away the "honour" of US troops and that they "betrayed" American credibility. He suggested that a small number of specialised troops in Syria was the only thing preventing a genocide.

Other candidates on the debate stage took turns to slam Mr Trump for abandoning America’s allies and damaging US credibility across the world, in the eyes of friends and foes.

Elizabeth Warren said she believed the US had to get out of the Middle East and should not have troops there, but needed to do it the right way by negotiating a solution. “This president created a bigger than ever humanitarian crisis,” said the Massachusetts senator.

Vermont Senator Bernie Sanders, who has long criticised and voted against military interventions in the Middle East, said Turkey was not a US ally when it invaded another country and engaged in “mass slaughter”. He said Mr Trump's actions would result in no country trusting the word of the United States or believe “this pathological liar”, referring to the president.

Kamala Harris, a senator from California, said Mr Trump had given thousands of Isis prisoners a "get out of jail card” and suggested that the winners of the latest move are Russia, Bashar al-Assad, Iran and Isis.

Former vice-president Joe Biden called Mr Trump’s move “the most shameful thing” that any president had done in modern history and said US commanders across the board were ashamed.

In response to Ms Gabbard, he said that the US policy in Syria was not about regime change, but making sure the regime did not “wipe people out” in the border area.

Mr Biden said that if Isis prisoners escaped, they would go back to Europe, adding that some could make it to the US.

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Beto O'Rourke, a former congressman from Texas, picked up on that point saying the United States may have to send “another generation of American soldiers” back to fight Isis. He also suggested the US should invest more in diplomacy and the state department, to be able to rely more on the experience of diplomats rather than on soldiers aged 18 or 19.