When a freshly inaugurated Donald Trump issued his infamous travel ban exactly one year ago, the message was clear, not only to Muslims but to the entire world, that the United States was suddenly a very different place. But in some way, the policy can be viewed as just an official confirmation of a disturbing resurgence of a reality as old as travel itself: Members of certain communities are explicitly unwelcome by others.

The history often begins closer to home, for domestic travelers. Writing for The Washington Post, journalist Rhonda Colvin explains how, decades ago, African-American families would never travel without the Negro Motorist Green Book, a "survival tool" that listed restaurants, gas stations, hotels, pharmacies and other places they could safely stop at. "Black travelers risked more than the humiliation of being turned away at restaurants or service stations; they often encountered harassment or physical danger if they inadvertently stopped in the wrong town," Colvin writes.

But sadly, in recent years, discriminatory practices have returned to the surface in the age of social media and Airbnb, as direct person-to-person lodging platforms have revealed that would-be hosts refuse to rent to African Americans and other minorities.

But though the internet might have played a role in the resurgence of this scourge, it seems it's also providing those affected with a means to fight back. After having experienced racism first-hand on Airbnb, Rohan Gilkes founded Innclusive (formerly Noirebnb), which bills itself as a "platform where people of all backgrounds can travel and stay with respect, dignity, and love." Another, unrelated initiative named Noirbnb, clearly states however that its target audience is black people only.

And it's a juicy business too.

The same goes for other minorities and communities. Writing for Swiss daily Le Temps, Boris Busslinger reports that similar initiatives exist for Jewish people (Jewgether), gay people (Misterb&b) and Muslims — among many others. Muzbnb, a U.S.-based platform that lets Muslim proprietors rent to Muslim travelers around the world, is expanding fast and now entering the Swiss market, Busslinger writes. And it's a juicy business too. According to the Global Muslim Travel Index, Muslim tourism worldwide could be worth $220 billion by 2020.

One of Airbnb's "diversity ads" — Photo: Airbnb

Some, however, are pointing out the potential danger that these initiatives may encourage a "drift" toward ethnic or religious groups shutting themselves off from others, as Busslinger puts it. Saïda Keller-Messahli, a Swiss-Tunisian who received the 2016 Human Rights Prize in Switzerland, warns for instance that Muzbnb "promotes parallel society and sectarianism," while denouncing the fact that members of the Muslim Brotherhood are involved in the project.

It's a sad irony that in a time when traveling has never been easier and when the world has never been smaller, more and more people have the feeling they have to retreat inside their own communities to travel safely. Because traveling also entails being confronted to the unknown, the Other, in a much more direct way than across the screen of your computer or smartphone. It's yet another sign that no matter how technologies may simplify our lives, the human experiment remains as complicated as ever.

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