The official 'day of rage' demonstrations over Pope Benedict the XVI's Regensburg address are behind us, and a deluge of Muslim—Christian dialogue engagements (starting here; etc.; etc.)  loom ahead. But a taboo subject remains unraised, something far more inflammatory than what the pontiff actually said, and yet directly linked to his words.

Following the unhinged violence and hateful displays that have transpired across the Muslim world since the Pope's 9/12/06 lecture, no one desires to further incite any hair—trigger moderate Muslim leaders, or individuals, whose seething passions may just now, thankfully, have ebbed (for the moment). But for closure, or at least full disclosure, there remains one elephantine aspect of the offending late 14th century exchange between the Byzantine ruler Manuel II Paleologus and his learned Muslim interlocutor that has not yet entered the public discourse.

The implications of this omitted, oddly taboo discussion, are profound, transcending any concerns about its potential inflammatory nature.

At the end of the 26—round marathon dialogue of seven centuries ago alluded to by Pope Benedict, the Muslim 'muderris' (theologian), overwhelmed by continuous glimpses of Christian truth, hovers at the threshold of abandoning Islam and embracing Christianity. The muderris openly marvels at the magnificence of Christ and the Christian teachings, while proclaiming his readiness to journey to Constantinople (the last significant stronghold of the once mighty Byzantine Christian empire), and study with the theologians there. The drama of the dialogue thus concludes with the muderris' effective inner conversion to Christianity, and his promise to Manuel II to pursue this profound change of heart.

Today, (9/25/06) in the papal summer residence of Castel Gandolfo, Pope Benedict met with Muslim ambassadors Muslim ambassadors representing a broad spectrum of Islamic nations, hoping to assuage some of the anger over his Regensburg remarks. The inflamed jihadist passions throughout the contemporary Islamic world in the aftermath of the Regensburg comments—threats on the life of the Pope ('Pakistanis protest, cleric says Pope should be crucified' ) , or predictions that the 'Green flag of Allah will fly over the Vatican'—recall the Vatican's own early tribulations under physical, as opposed to mere verbal attacks from the true believers in jihad.

In 846 a fleet of Arab jihadists arrived at the mouth of the Tiber, made their way to Rome, sacked the city, and carried away from the basilica of St. Peter all of the gold and silver it contained. This was a typical Muslim jihad naval razzia. Earlier, by 827, the Arabs had conquered Sicily, which they kept under their suzerainty for two and a half centuries. Thus was Rome itself under serious threat from a nearby Muslim colony.

During the same ninth century when Rome was assaulted and Sicily was conquered, the Muslim armies occupied Bari and Brindisi in Italy, for thirty years; Taranto for forty; Benevento for ten; they attacked Naples, Capua, Calabria, and Sardinia several times; they put the abbey of Montecassino to fire and the sword; they even made razzias into northern Italy, arriving from Spain and crossing over the Alps.

In 847, the year after the aforementioned naval assault on Rome, the newly elected Pope Leo IV began the construction of walls around the entire perimeter of the Vatican, 12 meters high and equipped with 44 towers. He completed the project in six years. These are the 'Leonine' walls, and significant traces of them still remain. But precious few today understand that these walls were erected to defend the Holy See of Peter from an Islamic jihad. And many of those who do know this remain silent out of misplaced discretion. As Vatican reporter Sandro Magister has observed,

'Bridges, not walls' is the fashionable slogan today.

But is Pope Benedict XVI willing to pursue the 'Bridges' rhetoric to the same logical conclusion drawn by todays Islamic religious and political leaders, and in turn, consistent with the indomitable spirit of Manuel II Paleologus, who gamely presided over a Byzantine Empire in its death throes, even seeking to win spiritual 'converts' among his Muslim adversaries to the bitter end? Will proselytization, with the ultimate goal of gaining new converts, remain unidirectional—boundless petro—dollar funded opportunities for Muslim da'wa, linked to frank colonization in the West, including Rome itself (i.e., no longer merely 'nearby' colonization as in 9th century Muslim—ruled Sicily), while Catholic (and other Christian) missionary work in Islamic nations remains prohibited, often via state sanctioned violence, and draconian punishments for any such 'unregulated' efforts?

Manuel II's was a voice from the doomed—a near terminal plea for faith in a reasonable God by the leader a thousand year old civilization on the brink of destruction.  Last weekend an Italian nun—assassinated by jihadists in Mogadishu enraged by Benedict XVI's address—spoke 'forgive!'  as she gasped her final breaths. Will this Pope muster the courage of their convictions, charting a new direction for his flock, and by example, Western civilization, that averts a similar fate?

Let us—even atheists like myself—pray.

Andrew G. Bostom is the author of The Legacy of Jihad and a frequent contributor to American Thinker.