While President Donald Trump unveiled his plan on the US's role in Afghanistan, much of which is still shrouded in secrecy, his senior advisers reportedly employed a novel approach to help persuade him in making his final decision, according to aWashington Post report Monday.

National Security Adviser H.R. McMaster, who still serves as a lieutenant general in the US Army, was said to have shown Trump a black-and-white image from 1972 of Afghan women walking through Kabul in miniskirts, The Post reported Monday night.

McMaster ostensibly used the image to convince Trump that Western norms could return to the country, according to Post reporters Philip Rucker and Robert Costa.

Despite that image, Trump's Monday night speech on his Afghan war strategy emphasized that the US would not be “nation-building again,” and instead would be “killing terrorists.”

Trump had reportedly been weighing several options for the US's longest war, including the possibility of employing military contractors. Although McMaster initially advocated for sending tens of thousands of troops to Afghanistan, in addition to the 8,400 who are already deployed there, former chief strategist Steve Bannon was said to have opposed the idea.

Trump, who has talked frequently about his reverence for military generals, eventually opted for a modest troop increase, which is rumored to be around 4,000 service members.

“My original instinct was to pull out, and, historically, I like following my instincts,” Trump said. “But all of my life I heard that decisions are much different when you sit behind the desk in the Oval Office.”

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