ROME – Cue the soundtrack from film adaptations of the Dickens classic, because what Pope Francis has given us over the last week, ladies and gentlemen, is a Tale of Two Cities … only the settings aren’t London and Paris, they’re Beijing and Ankara.

We’re in the middle of July, which means most of Italy, including the Vatican, is down-shifting in preparation for the August holidays. Though a pope can make news anytime he wants, in reality about the only time he’s on the public stage right now is for his noontime Sunday Angelus address, and the last two have been humdingers.

Last Sunday, the headline was what the pope didn’t say. An advance text circulated by the Vatican included a passage about Hong Kong which Francis chose to skip, fueling endless speculation about whether China had somehow exercised pressure on the Vatican, or whether the pope maybe got cold feet.

Yesterday, by way of contrast, the story was what the pope did say that wasn’t in the advance text. He spoke out on Turkey’s decision to revert the fabled Christian basilica of Hagia Sophia from a museum to an active mosque, a move which had been strenuously resisted by Turkey’s small Christian community centering on the Patriarchate of Constantinople.

“I’m thinking of Santa Sophia … I am very pained,” he said, in language that did not appear in the advance version of his remarks circulated by the Vatican Press Office earlier Sunday morning.

So, the obvious question presents itself: Why did Francis speak out on Hagia Sophia, but bite his tongue on Hong Kong? In all likelihood, the distinction, at least in part, has to do with who’s most likely to be paying attention and most likely to be unhappy: Turkey, in the case of Hagia Sophia, and China with regard to Hong Kong.

In other words, it’s the difference between Ankara and Beijing.

To begin with, Turkey is a regional power while China is a global superpower. Diplomatically, there’s a lot more to lose in fraying relations with Beijing than Ankara.

That’s not to say Turkey is unimportant for the Vatican. Engaging the country is part of Rome’s broader strategy for empowering moderates across the Islamic world, and Turkey certainly played a pivotal role in affording Pope Benedict XVI a chance to mend fences shortly after the firestorm over his Regensburg address in 2006.

However, the Vatican didn’t just sign a deal with Turkey over the appointment of bishops that it hopes will lead to broader diplomatic relations, and which will shortly be up for renewal, possibly making this an inauspicious moment to upset the apple cart.

In addition, the Vatican aspires to being a voice of conscience in global affairs, and for that idea to be anything more than notional, Rome has to be in conversation with the world’s great powers, which, for better or worse, means safeguarding its relationship with China.

Second, there’s a substantial Catholic community in China, conventionally estimated at 13 million, and the pope – any pope – has to be concerned about the impact of his words or deeds for those believers. By way of contrast, the Catholic footprint in Turkey is fairly minimal – no more than about 50,000 souls.

Moreover, most students of religious demographics believe that China is potentially mission territory in a way that Turkey isn’t. Turkey is an overwhelmingly Muslim nation and, under Recep Tayyip Erdoğan, its Islamic identity is becoming progressively stronger. The decision to turn Hagia Sophia back into a mosque cuts in that direction.

In addition, China has no religious tradition that’s intimately bound with national identity. (Confucianism is an ethical code rather than a conventional religion). It’s a country where religion was suppressed forcibly for 70 years and now is bursting with spiritual energy, which, among other things, is why evangelical and Pentecostal Christianity has exploded there in the last quarter-century.

The pope, therefore, has to think not just about the Catholic community of today, but the potential for tomorrow.

There is a small but critically important Orthodox Christian footprint in Turkey, and that brings us to the third relevant difference: There was an ecumenical subtext when it comes to Hagia Sophia.

Both Patriarch Bartholomew of Constantinople, with whom Francis is close, and Patriarch Kirill of the Russian Orthodox Church, with whom Francis and the Vatican have been attempting to cultivate closer ties, had spoken out prior to the formal announcement of Turkey’s decision. Had Francis not addressed it publicly, it might have seemed he was leaving them alone.

Bottom line: The difference between last Sunday’s Angelus and yesterday may have less to do with the substance of the issues at stake, and more with the intended audience.

Purists, may object that popes shouldn’t engage in such calculations, but in reality it’s a gospel principle rooted in Matthew 10:16: “Behold, I am sending you like sheep in the midst of wolves; so be shrewd as serpents and simple as doves.”

Follow John Allen on Twitter at @JohnLAllenJr.