Manila - Philippine President Rodrigo Duterte has sanctioned a bloody drug war that features extrajudicial killing. He called ex US president Barack Obama a "son of a whore". This week, he boasted that he murdered a man with his own hands.All that went unmentioned in public by US President Donald Trump when the leaders held talks on November 13 in the Philippines.Reporters saw the beginning of the leaders' bilateral meeting in during which Trump praised Duterte's hospitality, the organisation of the summit he was hosting and even Manila's weather. Trump said nothing about human rights and both leaders ignored shouted questions about the violent drug crackdown. The two men also shared a laugh in the meeting when Duterte called reporters "spies".Later, White House Press Secretary Sarah Huckabee Sanders said that the 40-minute meeting focused on ISIS, illegal drugs and trade. Human rights, she added, briefly came up in the context of the Philippines' fight against illegal drugs. She did not say if Trump was critical of the violence.That appeared to conflict with the Philippines' version of the meeting. Harry Roque, a spokesperson for Duterte, said "there was no mention of human rights. There was no mention of extra-legal killings. There was only a rather lengthy discussion of the Philippine war on drugs with President Duterte doing most of the explaining."Breaking with his presidential predecessors, Trump has largely abandoned publicly pressing foreign leaders on human rights, instead showing a willingness to embrace international strongmen for strategic gain. He has cozied up to autocrats such as Saudi Arabia's King Salman, Egyptian President Abdel-Fattah el-Sissi and Russian President Vladimir Putin. And earlier in this trip to Asia he made no mention of human rights during multiple appearances in Beijing with Chinese President Xi Jinping."Trump seems very comfortable with strongmen. It's not just that he won't criticise Duterte. I wouldn't be surprised if he patted him on the back," said Mike Chinoy, senior fellow at US-China Institute at the University of Southern California, before the meeting.Duterte's war on drugs has alarmed human rights advocates around the world who say it has allowed police officers and vigilantes to ignore due process and to take justice into their own hands. Government officials estimate that well over 3 000 people, mostly drug users and dealers, have died in the ongoing crackdown. Human rights groups believe the victim total is far higher, perhaps closer to 9 000.'At the age of 16, I already killed someone'"Human rights groups, I think, will be quite disappointed by the visit," said Amy Searight, director of the Southeast Asia Programme at the Centre for Strategic and International Studies. "It's unlikely that human rights or rule of law or due process are going to be topics that President Trump will raise."Duterte has strenuously defended the violence and boasted of participating himself.Late in 2016, he bragged that he personally pulled the trigger and killed three people years ago while serving as mayor of Davao City. And last week, while in Vietnam for an international summit, he said he took his first life years earlier."When I was a teenager, I had been in and out of jail, rumble here and there", Duterte said during a speech in Danang, where he briefly crossed paths with Trump on the sidelines of an international summit. "At the age of 16, I already killed someone."He claimed he fatally stabbed the person "just over a look". His spokesperson later tried to downplay the comment, saying, "I think it was in jest".Trump has shown little interest in pressuring Duterte to rein in the violence, instead saluting him during a May phone call."I just wanted to congratulate you because I am hearing of the unbelievable job on the drug problem," Trump told Duterte, according to a transcript of the conversation that later leaked. "Many countries have the problem, we have a problem, but what a great job you are doing and I just wanted to call and tell you that."Trump also criticised Obama during the call, noting that his predecessor "did not understand" the drug problem the Philippines faces. Meanwhile, Duterte was openly critical of Obama in the final year of his presidency, including cursing his name.A good relationship is vital to the USWhite House officials have suggested there is a strategy behind Trump's flattery of Duterte.Advisers have said that while Trump was always unlikely to publicly chastise the Philippine president, he may offer criticisms behind closed doors. Trump would plan to hold his tongue in public in order not to embarrass Duterte, whom he is urging to help pressure North Korea and fight terrorism, and to avoid pushing him into the arms of China."If the administration is not going to care about human rights in China, why would you care in the Philippines?" asked Gordon Chang, Asia expert and author of "Nuclear Showdown: North Korea Takes On the World". He said the "logical thing to do is keep them close and not let Duterte flirt with China. In our struggle with China, we need all the friends when we can get".Human rights groups have expressed dismay at Trump's public silence, believing that the spotlight an American president can shine on human rights abuses overseas can rally pressure on an authoritarian regime to change its ways."In the old days, we used to call on the US government to raise human rights issues during these trips," said John Sifton, Asia advocacy director at Human Rights Watch. But given the administration's lack of credibility in raising human rights abuses, he said, they have pivoted to a different tack, focusing on international attention."We haven't given up," Sifton said.