The Gemara establishes in Masechet Berachot that when a person sees a king, he must recite a special Beracha. Upon seeing a Jewish king, one recites the Beracha, "Baruch Ata Hashem Elokenu Melech Ha’olam She’halak Mi’kebodo Li’yere’av," and upon seeing a non-Jewish king, the Beracha is, "Baruch Ata Hashem…She’natan Mi’kebodo Le’basar Va’dam."
The Radbaz (Rabbi David Ben Zimra, Egypt, 1479-1573) writes that a "king" is defined with respect to this Halacha as a ruler with the authority to order a death sentence. According to the Radbaz, this Beracha is recited only upon seeing a king who has the power to put somebody to death without being held accountable for it. Seemingly, then, this Halacha is limited to dictators, and the Beracha would not be recited over elected leaders in democratic countries, who quite obviously do not have the right to order a citizen’s execution.
Hacham Ovadia Yosef, however, rules that this Beracha is, in fact, recited upon seeing even the leader of a modern democratic country. He explains that although today’s leaders, such as the President of the United States, do not have the authority to execute citizens, they do have the authority to pardon a convicted criminal who had been sentenced to execution. This qualifies as life-and-death authority, such that a leader’s level of power indeed qualifies for the recitation of this Beracha. What’s more, Hacham Ovadia adds, the President has the power to declare war and to order military action, and thus truly does have the authority to kill. As such, the Beracha is warranted upon seeing the President.
In a different context, Hacham Ovadia establishes that this Beracha is recited only when the king is dressed in his royal garb. The text of the Beracha makes reference to "Kebodo" ("honor"), and thus the Beracha is recited only when one sees the king’s honor, when he is dressed in his special regal attire, such as a crown, medallions and such. At first glance, this ruling precludes the possibility of reciting the Beracha upon seeing the President of the United States, who, although he dresses formally, does not have special royal garments. However, Hacham Ovadia’s son, Hacham David Yosef, writes that if one sees the President with his entourage and security detail, accompanied by the usual fanfare of the presidency, this qualifies as "honor." The term "Kebodo" does not require specifically royal garb, but any expression of special honor for the nation’s leader. And therefore, even nowadays, if a President pays a visit with an entourage and the usual flurry of activity that surrounds presidential visits and functions, then those who see him on that occasion should, indeed, recite the Beracha of "She’natan Mikebodo Le’basar Va’dam."
It should be noted that the Gemara in Masechet Berachot teaches that one should "run" to seize opportunities to see kings, even non-Jewish kings. The reason is that when Mashiah comes, we should be familiar with ordinary rulers so that we can fully appreciate and value the greatness of Mashiah. Thus, those who have the opportunity to see the President of the United States should make an effort to do so.
Summary: One who sees the President of the United States accompanied by great honor – such as with his entourage and the usual fanfare of presidential functions – recites the Beracha, "Baruch Ata Hashem Elokenu Melech Ha’olam She’natan Mikebodo Le’basar Va’dam." Those who have the opportunity to see the President of the United States should make an effort to do so.
