German Chancellor Angela Merkel said she’s obliged to treat Donald Trump with respect because he won the U.S. presidential election fair and square, though she’ll vigorously pursue German interests when policies clash. “This is not about being friends or being in a family,” Merkel said on a panel in Berlin on Wednesday. “Each of us represents the interests of our countries and our citizens and we have to try to do as much as we can to advance these interests.” In a discussion that ranged from foreign policy to the chancellor’s reading habits, Merkel linked Trump’s election to a “fear of U.S. decline” and said he wasn’t simply handed the White House on a “silver platter.” Trump won under U.S. electoral laws and deserves respect “regardless of how I assess our opinions,” the chancellor said. Merkel’s expression of realpolitik comes as she struggles to build the kind of relationship with Trump that she had with his two predecessors. The U.S. president has assailed Germany’s trade surplus, pressed NATO allies to spend more on defense and withdrawn from the Paris climate accord. In May, Merkel questioned U.S. reliability that’s underpinned the trans-Atlantic alliance since World War II. With a national election ahead on Sept. 24, the chancellor’s main opponent, Martin Schulz, is stepping up his effort to link her and Trump on the campaign trail. The Social Democrat expanded his party’s attacks on Trump on Tuesday, pledging to ban U.S. nuclear weapons from Germany and portraying Merkel as bowing to U.S. pressure to increase defense outlays. On the Handelsblatt newspaper panel, Merkel said Germany’s obligation is to a 2014 pledge by all NATO countries to increase defense spending “towards” 2 percent of economic output. “This has absolutely nothing to do with the current president,” she said. In expansive comments on the state of the U.S., Merkel expressed understanding for Americans who feel left behind and were confronted with wars that the country “didn’t clearly win.” “The insecurity comes from this idea that America is taking care of everything in the world, but not for us here in our states, where we have unemployment, we don’t have health care, or other things,” Merkel said, referring to her impression of U.S. voters. Merkel spoke of the difficulty of reaching compromise with other world leaders, recalling talks at a Group of Eight summit in 2007 in Germany. Pressured to forge a deal on climate amid objections from by former President George W. Bush, leaders including then-U.K. Prime Minister Tony Blair managed find the right language in the final statement. “George Bush was also perfectly prepared,” Merkel said.