When I travel abroad, I try to err on the side of offering too many "yes, pleases" and "thank yous." I wouldn't wear a T-shirt if my itinerary included a historical church or temple or mosque, and if I'm confused as to whether the gratuity is included, I make sure to at least leave a stipend. If the local language is something other than English, I'll make the effort to say "good morning" or "good evening" in the native tongue. I'm ever mindful that whenever I am beyond my natural borders, I'm a representative of the United States, albeit just one of more than 300 million without portfolio.

Still, in my own small way, I try to do my part to dispel the image and false stereotype of the ugly American. The aggressive, pushy know-it-all epitomized by Ryan Lochte, the Olympic swimmer who in 2016 was charged with filing a false police report in Rio de Janeiro during the Olympics after claiming he'd been robbed by men with police badges. Brazilian authorities said Lochte and swimming teammates were intoxicated and vandalized a gas station.

On a few occasions, when venturing far off the beaten path, I've had occasion to be the only American someone has ever met. Despite the short distance of just 90 miles, that was my experience a few times last summer in the center of Cuba. Even where Americans have visited often, the world mostly knows us by our exported culture: our movies, music, and celebrities. The internet has fueled that process via Apple, Amazon, and Netflix. Often these represent us in a false light, increasing the importance of personal impressions.

My efforts seemed an exercise in futility recently. No amount of person-to-person encounters this summer travel season can offset the recent actions of our president, a point about which I was reminded while traveling briefly in the United Kingdom. Prior to my departure, President Trump sent a vulgar tweet commenting on the plastic surgery of Mika Brzezinski, cohost of MSNBC's Morning Joe. By the time I'd landed, he'd  tweeted an internet meme that showed him body-slamming CNN. His impulsivity apparently wasn't slowed by the fact that the meme originated on Reddit via someone whose online identity is "HansA–Solo." Nor was the president deterred by this individual's prior listing of CNN personalities next to Stars of David, an anti-Semitic suggestion of overrepresentation in the media.

"Hans" has since apologized. The president has not. No wonder much of the domestic debate has been about whether the meme will be violence-inducing. For the sake of my colleagues and me at the cable outlet, I sure hope not.

While traveling, I was reminded that his behavior transcends our borders. And it's utterly embarrassing. The big local story in England is Wimbledon. But Trump's tweet has been "the" story from America. It was covered extensively on British television and in newspapers, as was his attack on Brzezinski. And both were a source of befuddlement to several Brits with whom I spoke, including during a visit to Borough Market, scene of a bloody attack June 3 by three radical Islamists who killed eight people. (Spending money there in support of #LondonIsOpen was another of my voluntary ambassadorial undertakings.) My Anglo friends don't get the commander in chief, partly because for many, CNN International is their clearest daily window into America.

My London hotel room television had many offerings that were global in reach. Various BBC channels, Russia Today (RT), and Al Jazeera to name a few. As has often been my experience when traveling abroad, among the American cable offerings, only CNN was available. No Fox News — at least not the American version, and no MSNBC. CNN International is the only one with a global footprint, a point perhaps not considered by the president when circulating the image of him body-slamming the network logo. I doubt he considered that consequence when hitting the send key. Or maybe maintaining a position of global leadership and respect is unimportant to him.

When the president attacks CNN, he is trying to pillory a news source that is viewed and respected worldwide, including by foreign leaders, a point I was reminded of by email from Sen. Chris Coons (D., Del.) a few months ago.

"On Easter weekend, I was in Uganda and South Sudan, visiting refugee camps and humanitarian organizations," he wrote.  "As part of trying to address the civil war and resulting famine in South Sudan, I met with President Salva Kiir in his office in Juba. I had been forewarned he likes to keep his TV on during state visits. Imagine my surprise when you came on CNN during our otherwise tense visit while I was pressing him about humanitarian access and political reconciliation. I just wanted to let you know your reach is truly global, and it was encouraging to feel as if I had a friend in the room!"

By the time I landed in Philadelphia, North Korea was claiming to have tested an intercontinental ballistic missile. And the president was seeking global partners to do something about Kim Jong Un. Too bad they've already seen his recent video, too.

Michael Smerconish can be heard 9 a.m. to noon on SiriusXM's POTUS Channel 124. He hosts Smerconish at 9 a.m. Saturdays on CNN. @smerconish