Is there a specific, designated place where Moshiach will appear?

The Talmud relates that Rabbi Yehoshua ben Levi met Moshiach at the entrance of Rome, ready to reveal himself as Moshiach.

The question is, why was Moshiach precisely in that place? Of all places in the world, why did Moshiach choose to be revealed in Rome? According to Rashi's interpretation, the "entrance to Rome" referred to in the story is allegorical, not literal. However, the question still stands. What is the symbolism of Moshiach revealing himself at the entrance of Rome?

The Lubavitcher Rebbe explains: In Maimonides, in his monumental halachic work Mishneh Torah, describes the future Moshiach as a king who will teach Torah and lead the Jewish People, repairing any breaches in mitzvah observance. It naturally follows that Moshiach will reside in the place where the majority of Jews live in his day, in order to influence the maximal number of people.

This explains why, in the time of Rabbi Yehoshua, Moshiach chose to make his symbolic appearance near the entrance of Rome. In that generation, the majority of Jewish people were under Roman rule. So, too, in every generation there is an individual who is worthy of being Moshiach, who lives in the place with the greatest concentration of Jews and puts forth all his effort to draw the Jewish People close to Torah.

[There are sources that negate the possibility of Moshiach appearing outside of the land of Israel; however, they are not decisive halachic works. The only work of halachah that deals with this issue is Maimonides, who does not mention that Moshiach can appear only in the land of Israel. Therefore, we can assume that it is a possibility that Moshiach will appear somewhere in the United States, since that is where the majority of Jews reside, at present.]