So more like Google, Microsoft, Amazon, Salesforce, and most big tech companies than either Pizza Hut or Raytheon? Perhaps most like Red Hat (who also sell to the DoD)?

I think it would be unusual to call them all military contractors (as you called Canonical in another comment).

Ubuntu happily sells support contracts to whoever wants to buy them, yes. You can buy the same product the DoD does, it is not special. There is no "secret ubuntu distro for the DoD" by any stretch of the imagination.

The only thing the DoD cares about when it comes to an OS is that it is STIG'd and supported. RedHat and Canonical make a lot of money via support contracts for DoD programs.

Canonical == RedHat == Microsoft for the point you're trying to make, and that point is incorrect.

I hate ubuntu, in no way am I defending Canonical. If Iran thinks DDoSing Canonical will further a cause of their, it would be a second order effect, not just "because Canonical."