There's an important point missed in all the pearl-clutching by partisans on both sides about the allegations that a portion of Melania Trump's speech was plagiarized from a speech by Michelle Obama. The Trump campaign has denied the speech was plagiarized. They might as well have asked what difference, at this point, does it make.
The portion of the speech was about the "values" Obama (or Trump) share with their spouse: working hard for what you want, keeping your word, and treating people with respect (in Obama's case, clarified to include those you don't know or disagree with).
Both President Obama and Donald Trump have shown through their actions that these values don't mean all that much to them, illustrating an important lesson on the meaninglessness of politicians' words.
Obama ran for re-election in part on the idea that if you owned something you were proud of (something, even, that you might have worked hard to get because you wanted it), "you didn't build that."
Even liberal fact-checkers have lists of Obama's broken promises. Most prominently perhaps, Gitmo is still open. There was also all the obfuscation over what the Affordable Care Act actually was (with the Supreme Court eventually saving the legislation by ruling, more or less, that it was a tax, the opposite of what its supporters claimed it to be)
As for the line about "treating people with respect," as David Harsanyi noted in a column last week that Obama has a tendency of framing his ideological opponents not merely as well-intentioned people who disagree with him but as people with problematic moral compasses, whatever the issue. He consistently belittles opposition. His vice president gleefully called Republicans terrorists.
Donald Trump's hardly a living example of the values Michelle and Melania articulated either. Trump has yet to be in charge of any government tax bureau, but he has used and supported eminent domain (greasing political palms, which Trump happily admits to, is hardly hard work) to take property he wants from people who have worked hard to get what they wanted and don't want to sell it to him.
Is his word his bond? Trump has managed to give his word and go back on it in the span of a few minutes numerous times. He's been on both sides of many issues, sometimes at the same time.