As I watched Donald Trump announce that the United States would recognize Jerusalem as Israel's capital and move our embassy to that city, I could only think of one thing: my high school youth group Bible study.

I know that sounds odd. Especially coming from a liberal Episcopalian like me. But there you have it. The President makes a world-important declaration about global politics, and an absurdly apocalyptic thought arises, "Jerusalem? The Last Days must be at hand!"

When I was a teenager in the 1970s, I attended a "Bible church," a nondenominational congregation that prided itself on a singular devotion to scripture. We read the Bible all the time: in personal Bible study and evening Bible classes. We listened to hourlong Sunday morning sermons. For us, the Bible was not just a guide to piety. It also revealed God's plan for history. Through it, we learned how God had worked in the past and what God would do in the future.

Central to that plan was Jerusalem, the city of peace, and the dwelling place of God. It was special to the Jews because it was the home of Abraham and David. It was special to us because it was where Jesus had died and risen. We believed that ultimately, Christ would return to Jerusalem to rule as its king. We longed for this outcome -- and we prayed that human history would help bring about this biblical conclusion.

Jerusalem was our prophetic bellwether. God's plan hung on its fate. Whenever Israel gained more political territory, whenever Israel extended its boundaries, it was God's will, the end-times unfolding on the evening news. Jerusalem, as the spiritual heart of Israel, mattered. Jerusalem was God's holy city, of the ancient past, in its conflicted present, and for the biblical future.

For many conservative evangelicals, Jerusalem is not about politics. It is not about peace plans or Palestinians or two-state solutions. It is about prophecy. About the Bible. And, most certainly, it is about the end-times.

When I was young, our pastor insisted that Jerusalem had an important role to play in these end-times events. When the Jews rejected Jesus as the messiah, he explained, God chose the church to accomplish his mission. Soon this "church age" would end with the rapture of true believers.

But God still loved the Jews, he told us, and wanted to redeem them. Thus, absent the church, the Jews would experience a great religious rebirth and rebuild their temple in Jerusalem. This would spark a series of cataclysmic events that would culminate in the Battle of Armageddon, the last war of humanity. But it would also cause the Jews to finally accept Jesus as their savior. After all this occurred, Jesus would return in glory and God's kingdom -- a thousand-year reign of peace. And it would begin in Jerusalem.

This theology -- a literal belief that all these things must happen before Jesus will return to reign on Earth -- is called "dispensational pre-millennialism" and it is not the quirky opinion of some isolated church. Although the majority of Christians do not share these views, versions of dispensational pre-millennialism dominate American evangelicalism.

It originated as a small movement in the 1840s, but by the 1970s, millions of evangelical and fundamentalist churchgoers had embraced some form of it. Dispensationalism was popularized in a best-selling book called "The Late, Great Planet Earth" by Hal Lindsey; and later, in the 1990s, it reached an even larger audience through the "Left Behind" novels by Tim LaHaye and Jerry Jenkins. The theology spread via Bible camps and colleges, through theological seminaries and revival meetings, in films and videos, by Sunday school materials, and in daily devotional guides -- all teaching that the end of the world was near, and that Jerusalem was the physical place where this apocalyptic drama would unfold.

If you know evangelicals, chances are very good that you know this theology, whether you believe it or not. You cannot avoid it. And if you hear the President of the United States say something about Jerusalem, you take notice. Especially when that President won 81% of the white evangelical vote.

When the President issued his order, I was not the only person hearing echoes of dispensationalism. Robert Jeffress, one of Trump's evangelical advisers, declared: "Jerusalem has been the object of the affection of both Jews and Christians down through history and the touchstone of prophecy."

Other evangelical pastors and teachers also praised the action as "biblical" and likened it to a "fulfilled prophecy."

While that may sound benign (or perhaps nutty) to the theologically uninitiated, they are referring to the "prophecy" of the conversion of the Jews, the second coming of Jesus, the final judgment, and the end of the world -- the events referred to as the biblical apocalypse.

I doubt that President Trump could explain dispensational pre-millennialism. I doubt he knows the term. But his evangelical supporters know it. Some of his advisers are probably whispering these prophecies in his ears. Trump might not really care how they interpret the Bible, but he cares that white evangelicals continue to stand with him. Moving the embassy to Jerusalem is one way to affirm his commitment to these evangelicals -- reminding them that he, Donald J. Trump, is pressing biblical history forward to its conclusion and that he is God's man in the unfolding of these last days.

I may not believe it -- anymore, at least. You may not believe it. Donald Trump might not even truly believe it. But millions do. That matters. Not only for American politics, of course. For the peace of Jerusalem. And for peace for the rest of us as well.