On an unrelated errand we were looking up how much the US spends on its defense. We made the terrible mistake of just Googling it. But hey, that mistake turned into an insight we can share!

Turns out a lot of different people have very different ideas of how much the US spends on its defense as a percent of the Federal Budget. So let’s play a game.

Before we start: Guess your own number. Just for fun. Don’t need to share it with anyone, no “I told you so’s,” no points won or lost.

Here’s a picture of a fighter jet to give you time to think before seeing the numbers.

Now that you’re done, let’s look at what different reputable and not-so-reputable sources say. (Click images for links.)

More Reputable

Pew – 15% (2016)

American Enterprise Institute – 14% (2016)

Huffington Post – 34% (2015)

$1.3T out of a $3.8T budget

Less Reputable

USGovernmentspending.com – 22% (2015)

War Resisters League – 28% or 48% (2015)

Some Blogger Named The Lunatic – 40% (2015)

American Friends Service Committee – 57% (2017)

Some Other Blogger Named Mike – 57% (2013)

(This one has been popular on social media.)

Nation of Change – 66.3% (2017)

Later they say 21.7% of the whole but say this is “misleading”

What’s the CBO Say? 15.7% (2015)

They peg it at 15.7% (3.3% of a GDP of just over $18T and a budget of $3.8T) – and that’s actually projected to decrease as a percentage of GDP and budget over the next 10 years (based on 2015 policy). It’s down about 1/3 since 1990. See page 81 of the report.

What Gives?

I’m not going to tell you who’s “right” and who’s “wrong” because it all depends on how you count it. Do you or do you not include:

• Emergency war spending?
• Foreign aid?
• The Defense Department’s janitors?
• Veterans’ Benefits?
• The CIA/NSA/other intelligence services?
• NASA and DARPA R&D (which might be used for military purposes)?
• Corporate tax breaks?
• Net interest, either somehow apportioned for past military spending–or all of it?

Even including all of that we have no idea how one gets to 48%+ of total federal budget, but we decied not to dig into the math.

Point is you can chop this up a lot of ways, and so somewhat reputable folks can come up with different numbers, and not be “wrong” based on whatever assumptions they have. The CBO may not even have it “right” based on what you want to put into the bucket.

The Other Trick: The Discretionary Sneak

The 57% number got very popular in 2015 sliding around the Internet. Turns out it’s an image of only discretionary funding (rather than mandatory), and discretionary is not the whole picture: discretionary + mandatory is the full budget. Politifact breaks it down (and even the 57% of discretionary is apparently wrong). They fall in on 16%.

Either through simple laziness and carelessness, or confirmation bias, or pushing an agenda, some folks spread around the 57% number–and other people, for the same reasons, believed it.

This all goes to show: it’s easy to get duped when you’re excited about getting mad about a fact.