HE was almost lost in the whirl of lawmakers, pundits, plutocrats and other boldface names who showed up for Benjamin Netanyahu’s speech to Congress last week. But the presence of Pat Boone was a key to understanding why John Boehner was playing a smart game of party politics to stand so solidly with the Israeli prime minister.

I’m referring to Boone the singer. But I really mean Boone the churchman. He’s a prominent figure among, and megaphone for, American’s evangelical Christians, who listened to Netanyahu’s remarks as closely and adoringly as any constituency in this country.

For the speech, Boone wore a tie on which the flag of Israel, with its Star of David, was conspicuous. Just afterward, he told David Weigel of Bloomberg Politics that he’d known Netanyahu personally for years and had held some hope that the prime minister would give him a special shout-out during the remarks.

And days earlier, on a radio show, Boone described Netanyahu as a friend who was well aware that evangelical Christians constitute some of “Israel’s most staunch supporters,” numbering “in the tens of millions in the United States.”

He’s correct in that analysis, which was strangely missing from much of the media coverage of and commentary about the Netanyahu-Boehner alliance.

Yes, Boehner’s invitation to Netanyahu, rendered independently of the White House, was a way to get under President Obama’s skin and in President Obama’s way. And, yes, that provocation was manna to the most conservative House Republicans, who sometimes chafe under Boehner’s leadership.

But they loved what Boehner did for an additional reason: It catered to the evangelical Christians who are an integral part of the party’s base, especially for lawmakers from the reddest states or districts. In fact, as Ashley Parker reported in The Times, Boehner’s caucus gave him a standing ovation last week even though he was bucking them by linking arms with Nancy Pelosi to pass a bill to fund the Department of Homeland Security.

The prompt for all that clapping? Representative Doug Lamborn, a Colorado Republican, spoke up to thank Boehner for weathering attacks from the White House in order to make Netanyahu’s speech happen.

What part of Colorado does Lamborn represent? Colorado Springs, which is a Republican stronghold, famous for its concentration of evangelical Christians.

JEWS in the Democratic Party are more divided on the actions that conservative Israeli leaders like Netanyahu have taken in defense of Israel than evangelical Christians in the Republican Party are.

And that helps to explain the tightened bond between Israel and Republicans over the last few decades.

We in the media often look past that to focus on the influence of a handful of rich Jewish Republican donors for whom Israel is a priority. Foremost among them is Sheldon Adelson, the casino magnate. He almost single-handedly kept Newt Gingrich’s 2012 campaign for the Republican presidential nomination financed and alive.

And a year ago, when Chris Christie joined other potential Republican presidential candidates to give speeches to the Republican Jewish Coalition, he had to ask Adelson’s forgiveness after using the phrase “occupied territories” in reference to land where Palestinians live but Israel maintains a military presence.

But the bigger story is Israel’s importance to evangelical Christians.

“Christian Zionism as a sentiment is not new,” said Dan Senor, a Republican foreign policy adviser who has traveled to Israel with Mitt Romney, Chris Christie and other Republican candidates. “But as a movement, it has grown exponentially in size and political sophistication over the past 15 years.”

In early 2013, when Obama nominated Chuck Hagel, a Republican, to become the next defense secretary, and Hagel’s support for Israel was called into question, one of the groups lobbying against him in greatest number and at greatest volume was Christians United for Israel.

Its founder and chairman, John Hagee, was in Washington, D.C., with his wife last week at Netanyahu’s speech. They were Adelson’s guests.

Senor told me that in 2009, when he was promoting a book that he co-wrote, “Start-Up Nation,” about the modern Israeli economy, Christian radio shows extended as many invitations to him as Jewish groups did.

Some evangelical Christians’ interest in Israel reflects an interpretation of the Bible’s prophetic passages that’s known as premillennial dispensationalism. It maintains that the End of Days can play out as God intends only if Jews govern Israel and have reconstructed a temple on the Temple Mount, where there’s now a mosque.

But just a subset of evangelicals subscribe to that. Others are motivated by their belief, rooted in scripture, that God always intended Israel for Jews and that honoring that and keeping Israel safe is a way of honoring God. God’s blessing of America, they feel, cannot be divorced from America’s backing of Israel.

The conservative Christian television preacher Pat Robertson once publicly suggested that Ariel Sharon had suffered a stroke and that Yitzhak Rabin had been assassinated because both of these former Israeli prime ministers had pursued policies of “dividing God’s land.”

“There are evangelical connections to the land,” said Russell Moore, the president of the Ethics and Religious Liberty Commission of the Southern Baptist Convention.

It’s common for large evangelical congregations in the United States to organize tours of Israel for their members. Mike Huckabee, a Baptist pastor and probable candidate for the 2016 Republican presidential nomination, has been running something of a side business as a guide for American evangelicals with Galilee and the Garden of Gethsemane in their sights. “The man is just nuts about Israel,” William Booth wrote in a Washington Post story two weeks ago about Huckabee’s tours. Huckabee told Booth that he visits Israel as often as four times a year.

The attacks of 9/11 and the spreading threat of Islamic extremists have further strengthened American evangelicals’ sense of kinship with Jews in Israel, whom they see as crucial partners in fighting butchers who have recently singled out Christians for slaughter.

Moore told me that American evangelical leaders are routinely trying to get American lawmakers to focus on anti-Semitism around the globe. He said that when he joined the prominent evangelical pastor Rick Warren and the lawyer (and Clinton adversary) Ken Starr last week on a panel at Georgetown University to discuss religious issues, anti-Semitism came up immediately.

That’s a climate and a context that are essential to understanding fully the bear hug in which Boehner wrapped Bibi. He wasn’t merely welcoming a world leader. He was doing in the arena of foreign policy what he tries and sometimes fails to do with domestic issues: keeping the base in buoyant spirits.