Daniel W. Drezner is a professor of international politics at the Fletcher School of Law and Diplomacy at Tufts University and a regular contributor to PostEverything.

A protester who opposes arrivals of buses carrying largely women and children undocumented migrants for processing at the Murrieta Border Patrol Station holds a flag and watches counter-demonstrating Aztec dancers on July 4, 2014 in Murrieta, California. Alas, no one polled these guys to find out if they were “freedom conservatives” or a “liberty conservatives.” (Photo by David McNew/Getty Images)

I’m an academic to my bones, which means any time someone proposes a new typology, my heart goes aflutter.  Over at BuzzFeed, Ben Smith proposes a new way to think about the conservative movement:

I propose replacing the messy old terminology with a simple new vocabulary, one that has evolved organically, which has deep and consistent intellectual roots, no pejorative implications, and which political leaders use effortlessly and without reflecting. The division that will define the Republican Party for the next decade is the split between Liberty Conservatives and Freedom Conservatives.

The divide over Liberty and Freedom has a good linguistic pedigree. The former draws on a straight line that runs from the Declaration to modern libertarianism; the latter on one that goes from emancipation to George W. Bush, with a rather inconvenient detour through Roosevelt. They can both claim Lincoln, who spoke in the Gettysburg Address of a nation conceived in liberty, and undergoing a new birth of freedom.

The divide also maps to real, recent policy divides. For example: U.S. intervention in the Middle East; the sequester that capped federal spending; the National Security Agency’s spying on Americans. Freedom Conservatives back the aggressive security measures and, relatedly, oppose the spending cap. Liberty Conservatives are deeply skeptical of bombing and spying, and drove support for limited spending.

David Weigel likes it; Daniel Larison doesn’t.  Since both Smith and Weigel reference bulls*** artist extraordinaire Michael Goldfarb in their posts, I’m predisposed to not liking it… but think they’re on to something.

Of course, the academic in me also likes to see concepts like these tested against evidence.  And going forward, the best test of taxonomy works will be the defense budget.  Liberty conservatives will recall fondly that prior to World War II the United States embraced its geographical blessings and never maintained a large standing set of armed forces.  Freedom conservatives will recall fondly that the U.S. military establishment helped to deter the Soviet Union during the Cold War and afforded post-Cold War presidents the ability to shape the global order to benefit the United States.

As the defense budget encounters strictures it hasn’t seen since before 9/11, the service branches are starting to clear their throats very loudly to Congress that they can’t live with Reagan-era levels of defense spending.  Consider two stories that popped up in the last 24 hours.  The first, from the Navy Times:

Fighting back at repeated budget cuts to its nuclear power budget requests, two of the Navy’s top leaders warned Congress on Monday that the cuts can’t go on.

“This approach is no longer sustainable,” wrote Adm. Jon Greenert, chief of naval operations, and Adm. John Richardson, commander of Naval Reactors (NR), the entity responsible for all aspects of the Navy’s nuclear power program. They sent the letter to chairmen and ranking members of multiple House and Senate committees.

“The persistent cuts have put NR in the position of being unable to provide for a safe and reliable nuclear fleet, design and test the reactor plant for the Ohio Replacement Program, and safely and responsibly manage aging infrastructure and the facilities for processing naval spent nuclear fuel,” Greenert and Richardson wrote.

That sounds like en eye-opening kind of letter.  But the Air Force’s comparative advantage in lobbying Congress and the American public cannot be denied, and the New York Times’ Helene Cooper is the beneficiary:

The Air Force flew a reporter on one of its long-range strategic bombers to show off its abilities and to make a plea to Congress for money to preserve and upgrade the country’s aging fleet — 20-year-old B-2 stealth bombers, 28-year-old B-1s and 50-year-old B-52s — as military budget cuts and skepticism in some quarters threaten the planes’ future.

The Air Force frequently argues to Congress that bombers could save the United States from deploying thousands of troops or aircraft carriers to strike targets as far away as China and North Korea or sections of Iraq held by the Islamic State in Iraq and Syria, the Sunni extremist group known as ISIS. The B-1 could make the bombing runs in a single round trip from South Dakota, North Dakota, Louisiana or Texas. “Stretching our legs,” Lt. Col. Joseph Kramer, the Air Force pilot who coordinated the mission, called it….

Not everyone agrees that the solution is spending more money on aging bombers, or even that the bombers — originally conceived to counter the nuclear threat from the Soviet Union — are relevant today.

“Is there a justification for a strategic nuclear-capable long-range bomber? Definitely no,” said Gordon Adams, a professor of foreign policy at American University who oversaw military spending in the budget office of President Bill Clinton. “We have more than enough capacity to deter and strike if needed with nuclear-missile-carrying submarines.”

For freedom conservatives, this will be a simple issue; they’ll support more defense spending.  For liberty conservatives, this will be a slightly trickier issue.  On the one hand, this should be the kind of interest group pleading that they wail about when it comes to runaway government spending.  On the other hand, one of the ways that liberty conservatives have been trying to expand their appeal to the rest of the GOP (with uncertain results) is to talk somewhat more robustly on foreign policy and drop “Reagan!!” into the conversation at times.  So we’ll see if Smith’s typology holds up going forward.

A coda:  I’m very curious to see how this issue of defense spending intersects with the group of “reform conservatives” that Sam Tannenhaus profiled last Sunday.  Having read the piece, it was almost exclusively focused on domestic policy; national security and foreign policy were barely mentioned.  As Smith notes in his piece, “the Freedom Conservative elites — from Bill Kristol to John Bolton to Sheldon Adelson — care a lot about foreign policy. Many of the Liberty Conservative leaders have less theory in that realm than instinct — that they’re against it.”  Ideas do matter, and if libertycons want to get the upper hand, they’re going to need to bolster their intellectual apparatus on foreign affairs and national security.