At Nate Silver's 538.com, they describe the Republican electorate as a five-ring circus, composed of Libertarian, Tea Party, Evangelical, Establishment, and Moderate voters.  A candidate who can bring three of the rings together will be the winner.  Ted Cruz is the one who's doing it.

With his pastor/father Rafael leading the way, Cruz has taken the lead among Iowa religious voters away from Ben Carson.  Their affection for the fervently Christian Carson is not enough to overcome his obvious weakness as a commander in chief.  Santorum and Huckabee are his other competitors in this ring, and neither has Cruz's money or organization.  They're going nowhere, and evangelicals like to go with a winner, just like everyone else.  Cruz now has this bloc firmly in his grasp, and he's not letting go.

Marco Rubio is Cruz's main competition for the Tea Party ring, but Rubio is not putting in the time schmoozing with them that Iowans believe they're entitled to.  Cruz has a far superior organization in a state that greatly rewards it.  While Rubio seeks to bridge the Establishment/Tea Party divide, Cruz revels in denunciations of the Republican power elites.  He's Tea Party, born and bred, and it's paying off.

Cruz's third ring, the one that puts him over the top, is libertarian, where he competes with Rand Paul, a disappointingly tepid campaigner who seems a little lost.  Paul is going nowhere in a hurry, and he has to start thinking about winning re-election to the Senate.  It's entirely possible he may drop out and throw his support to Cruz, who largely shares his ideology.

Part of that ideology is an aversion to foreign adventures, crusades, and immersion in the endless civil wars of the Middle East.  When Cruz continues to insist he will not put an American army into the middle of this hellhole, he appeals to a very important bloc of Iowa voters.  As Michael Barone, who knows these things, states in The Almanac of American Politics, Iowa is "one of the most dovish, isolationist-prone states" in the Union.

As Colin Woodard points out, Iowa's political culture is that of the Midlands, and there is a very powerful streak of pacifism in that culture.  Midlanders are instinctively moderate on most issues.  If there is one thing they are immoderate about, it's war.

Originally Quaker, it is populated by large numbers of the descendants of German pietists – Mennonites, Amish, Dunkers, and others – who have hated war since before they came to this country and still hate it today.  They are the votes that will win Iowa for Cruz.

Cruz is "doing the full Grassley" – appearing in every one of Iowa's 99 counties.  He's not only speaking; he's listening and learning.  And one thing I’ll wager he's hearing is anger at the pointless loss of American lives in wars far away that accomplish nothing.

A win in Iowa would propel Cruz into the top tier in New Hampshire and set him up for a win in South Carolina, where Politico reports he's well on his way to cornering the Evangelical vote.  From there on to the SEC primary, and the nomination.

If you think Donald Trump can continue his one-man show, a gravity-defying high-wire act, and unite a majority of the Republican Party behind him, then you'll find this argument unpersuasive.  But if The Donald does start to fade, as he's apparently done in Iowa, Cruz is perfectly positioned to gobble up those votes.  And with Cruz as the nominee, it would be hard for Trump to justify a third-party run.

As for the general, the danger for the Republican does not lie in showing a reluctance for war.  On the contrary, the American people are in the process of seeing the results of a war in Afghanistan, a war in Iraq, and a military intervention in Libya.  What have we accomplished with all our blood and treasure?  We've helped create such a tangled mess that we're told the only solution is yet another intervention in a 1,300-year-old Arab civil war.  Destroy ISIS, yes, but not with an American army.

Republicans lost Congress in 2006 and the presidency in 2008 when they were beaten by antiwar Democrats.  After San Bernardino, the American people want a realistic and aggressive fight against Islamic terror.  But if the Republicans think the path back to the White House involves promotion of yet another war, they could be in for a rude awakening.

Ted Cruz would not let that happen.

Fritz Pettyjohn is a former Alaska legislator and a co-founder of the Balanced Budget Amendment Task Force.  He blogs daily at ReaganProject.com.