“To find convincing answers for the future,” she said, “it is good to know what we achieved in the past.”<br />Mr. Trump, the New Yorker, presented a large chunk of the North Tower of the World Trade Center where the first hijacked plane made impact on Sept. 11, 2001,<br />leading NATO allies for the first time to invoke the collective defense clause, Article V, which European leaders were hoping Mr. Trump would endorse.<br />Barely two hours later, Ms. Merkel was among the European leaders who greeted Mr. Trump coolly at NATO headquarters in Brussels, where few casual<br />words, let alone warm ones, were exchanged, as the new American president once again castigated allies for not paying their fair share of bills.<br />Chancellor Angela Merkel of Germany started Thursday in Berlin with the 44th president — the one she has called “dear Barack.” She spent the afternoon<br />in Brussels with the 45th, Donald J. Trump, whose election she greeted with a stern reminder to respect shared values like equality and freedom.<br />For European leaders like Ms. Merkel, striking a balance between coaxing Mr. Trump into a deeper understanding with<br />America’s traditional allies, while remaining true to their own political principles, is proving to be tricky.<br />She was with Mr. Obama, “the good American who everyone is already missing,”<br />and then with President Trump, “the other America which needs to be dealt with.<br />European Visits by Trump and Obama Are a Study in Contrasts -<br />By ALISON SMALEMAY 25, 2017<br />BERLIN — The contrast could not have been more stark.