Regardless of what one thinks about the current American policy on immigration being debated in the courts, many other countries already limit visitors based on nationality - especially those from the Jewish state. Writing at Israel Hayom, Martin Kramer says that many Muslim nations hypocritically practice exclusionary tactics:
[Bernard] Lewis, the great historian of the Middle East who last May turned 100, traveled extensively in Arab countries in the late 1930s and 1940s. Born in Britain to British-born parents, he traversed French-ruled Syria for his doctoral work, and then served in the British army in Arab lands during the Second World War. In 1949, at the age of 33, he was already a highly regarded academic authority on medieval Islam and a full professor at the University of London. The university gave him a year of study leave to travel in the Middle East. But the Arab reaction to the creation of Israel derailed his research plans.
Lewis explained what happened in an article published in 2006: "Virtually all the Arab governments announced that they would not give visas to Jews of any nationality. This was not furtive; it was public, proclaimed on the visa forms and in the tourist literature. They made it quite clear that people of the Jewish religion, no matter what their citizenship, would not be given visas or be permitted to enter any independent Arab country. Again, not a word of protest from anywhere..."
Today, Arab states do not ban Jews as such. They do ban Israelis. In fact, six of the seven states in Trump's executive order ban the entry of Israeli passport holders: Iran, Iraq, Libya, Sudan, Syria and Yemen. (So, too, do another 10 Muslim-majority states.) Those same six states also won't admit non-Israelis whose passports contain an Israeli visa. I'm not aware that the international community regards this as a particularly egregious affront to international norms. The governments of these countries regard every Israeli, whether Jewish or Arab, or any past visitor to Israel of any nationality, as a potential security threat. That's not irrational, since some of these governments have a record of threatening Israel through incitement, sponsorship of terrorism, and dubious weapons projects...
But the governments of states such as Iran have no cause to profess outrage . No one has practiced blanket exclusion on the basis of nationality as unremittingly, decade after decade, as they have, and they aren't likely to give it up any time soon. It would be unfortunate if this became the norm in the world. But it wouldn't mark much of a change in the Middle East.