You’d never know it from the 2016 presidential election, but Donald Trump and Hillary Clinton used to be something resembling friends. In fact, she even attended his 2005 marriage to current wife Melania Trump. You see, before they were sworn political enemies, the Clintons and the Trumps got along pretty well.

Pictures from Donald and Melania’s star-studded nuptials show Hillary and husband Bill Clinton posing with the newlyweds — and even laughing at something Donald was saying. Bo Dietl, a fellow guest at the wedding, once gave NPR__ a report from the front lines. “When Donald and Melania came out to greet a lot of the guests, I saw Hillary going over and… kissing them. And she was very pleasant with him,” he said.

donald trump hillary clinton getty images

Bill and Hillary at Donald and Melania’s wedding.

The Clintons had good reason to seem chummy with the Trumps, though. Donald had given more than $4,000 to Hillary’s Senate campaigns over the years and at least $100,000 to the Clinton Foundation, according to Politifact.

But Donald may have made these donations less out of friendship and more out of strategy. Gwenda Blair, author of The Trumps: Three Generations of Builders and a Presidential Candidate, told NPR the current President’s friendships are “always transactional and only transactional.” She elaborated, “He surrounds himself with people he perceives as winners — celebrities, sports stars, actors, entertainers. He wants to be, you know, literally in the picture with them.”

Michael D’Antonio, another Trump biographer, gave a similar appraisal of the real estate tycoon’s personal relationships. “Outside of family, it seems like every move he makes is calculated to benefit him in some way, either financially or politically,” he said. “You know, this is a guy who literally produces his life. So much of what we see is fiction. It’s a play, a drama of manners.”

And D’Antonio even brought in a pop culture analogy that seemed awfully apt, given the above information. “There is a Taylor Swift-Kanye West parallel when it comes to Hillary and Trump,” he observed. “They will go at each other viciously, and then I will not be surprised when I do see them reconcile and smile and shake hands at some party in the future.”