The 72-year-old president said he still held same attitude as he did in his youth - "even more so as president" of the country.
President Trump said one of the major accomplishments of his Asia trip was building better relationships with other countries. He said a charitable reading of the meeting would be that Duterte was alluding to human rights issues when he said the drug war was important as an issue of "human development". In return, US' chief rivals offered state-of-the-art weapons and large-scale investment deals.
Furthermore, they also aim to "promote the sharing of experiences, best practices and exchange of views" to strengthen anticorruption efforts and the implementation of domestic laws and regulations to combat and prevent corruption.
All of a sudden, the United States seemed on the verge of losing its oldest ally in Asia, with China rapidly filling in the vacuum.
Trump told reporters during his two days here that he has a "great relationship" with Duterte. The Filipino president, who has consistently shunned criticising Trump, has been visibly pleased.
Duterte took steps to thaw frosty relations with China after he won the presidency previous year. But the Philippines is a major non-NATO ally, meaning it has special treaty status with the USA, and the relationship between the two countries dates back to the 19th century and the Spanish-American War, when the US took control of the islands from Spain. They are both besieged populists, who present themselves as the true representative of "the people" against the liberal establishment.
Duterte was meeting with Putin for the first time since May. Duterte has recognised, albeit reluctantly, the significance of U.S. alliance in moments of crisis.
Philippine Defence Secretary Delfin Lorenzana, a former defence attache in Washington, thanked the United States for playing a "vital" role in defeating ISIL elements in Marawi.
Duterte won last year's presidential elections after promising to eradicate illegal drugs with an unprecedented crackdown that would see up to 100,000 people killed. Duterte's office issued a statement, saying he regretted the comment.
The two leaders will also tackle continued cooperation in areas of disaster relief and humanitarian assistance, given the Philippines' vulnerability to extreme weather events. Human rights groups believe the total could be closer to 9,000. Responding to the criticism, Mr Duterte recently moved to take his controversial drugs campaign out of direct control of the police.
Duterte often seeks to have visitors pose for photos with him doing the salute, with Chinese internet tycoon Jack Ma and Hollywood actor Steven Seagal among those pictured doing so.
Trump did not publicly take Duterte to task for the crackdown.
But, given Trump's affection for strongman leaders, Duterte will most likely receive a free pass on murdering his own citizens.