The media is focusing on the Turkish-Armenian relationship and the politics of the 1915 genocide.
It's an interesting issue for a pope to tackle, especially considering one of his predecessors as almost assassinated by a Right-wing Turk affiliated with the Grey Wolves. The story of the assassination attempt on John Paul II is fraught with controversy. The Bulgarian-KGB story is riddled with problems but that's for another discussion.
Actually by agitating Ankara, Francis will likely cause difficulties for some of the Christian communities within Turkey. The goals of the great Orthodox Council (already in jeopardy of failure) won't be helped by the Latin Pope interfering in the region. Francis for his part is trying to reach out to the Orthodox world and score points as it were. The Armenians are somewhat unique in that as Monophysites they actually fall outside the mainstream Orthodox orbit.
But I think the real reason behind the visit is Russia. While on the one hand Moscow will enjoy Turkey's irritation they are likely a little apprehensive about the Roman pontiff visiting the region, a nation in which they have military bases. Armenia is within the Russian orbit and yet the two nations have not been entirely pleased with each other as of late. Anti-Russian sentiment is generally low in Armenia but it has been growing. I'm sure the West is funneling money into these causes and its leadership. The Caucasus have always been filled with intrigue but it's especially intense at present. American money and agents are flooding the region. Armenia is something of a wild card with a large expatriate population in the United States. And yet the politics are tricky. The US needs Turkey and Azerbaijan. And then there's the Chechens...
The Pope's visit may come with some incentives and he may be acting as something of a go-between, trying to reach out and possibly set up some diplomatic initiatives. It wouldn't be the first time he's done so.
It's not likely that Yerevan will be wooed away from the Russian orbit but the West is trying to do all it can to build support and establish contacts in the region. I'm sure the CIA is also utilising members of the expatriate community in the United States to foster these relationships. It wouldn't be anything new.
While the present Pope is often decried as a Leftist and some would think of him as anti-American this is not the case. Bergoglio and his background have been misunderstood. This is in addition to a woeful ignorance of Washington's very deep relationship with the Vatican. It didn't start with John Paul II.
Turkey is an essential NATO ally but Washington would rather see Erdogan gone and is working against him on many fronts. Pardon the cliché but 'Byzantine' accurately describes the politics of the region. It's a complicated tangle of history, theological claims and modern geopolitics.
I also find it interesting that Francis met with Russian Patriarch Kirill back in February. While in some ways it looks like he's on an ecumenical barnstorm, in fact Francis is now starting to poke around in Kirill's backyard.