Are Call of Duty Black Ops and Modern Warfare in the same universe?

So [MW2] is 3 years before [BO2] : r/CallOfDuty

Preparing for the New Era of Call of Duty®, Presented by Infinity Ward

How Call Of Duty: Black Ops Cold War Connects To Modern Warfare - GameSpot

Feature: All the Intel You Need on the Reimagined World of Call of Duty®: Modern Warfare® Special Ops.

Are all the Call of Duty games within the same universe? - Quora

Call of Duty Cinematic Universe plotted out for many years says Activision

Call of Duty: Ghosts is set “in its own world” with its “own timeline”, separate from Black Ops and Modern Warfare

Call of Duty: Black Ops -- Cold War review -- Putting the player on a treadmill

The 10 Best Call of Duty Campaigns - IGN