As America’s recent intervention in Iraq gathers steam, the phrase and its implicit warnings have reemerged among policymakers and public commentators. Worryingly, though, it seems some top officials don’t get it. As President Barack Obama noted on Tuesday: “Typically, what happens with mission creep is when we start deciding that we’re the ones who have to do it all ourselves. And because of the excellence of our military that can work for a time. We learned that in Iraq.” This is a puzzling lesson to take away from Iraq: rather than preferring unilateralism, the Bush administration begged every country with deployable military forces to participate in the invasion and occupation.

On Wednesday, Pentagon spokesperson Rear Adm. John Kirby offered a more concise definition: “mission creep doesn’t refer to numbers of sorties, numbers of troops, numbers of anything. It doesn’t refer to timelines. It doesn’t even refer to intensity. It’s about the mission itself.” This is true in the technical sense of how the Pentagon defines a mission: “The task, together with the purpose, that clearly indicates the action to be taken and the reason therefore.”

The problem with relying upon U.S. officials’ articulation and description of military missions is that there is a time-honored history of denying, dissembling, or outright lying about mission creep — while it occurs. This includes the U.S. bombing of 113,716 sites in Cambodia between 1965 to 1973 while the Johnson and Nixon administrations claimed otherwise; Reagan’s deployment of 1,800 Marines to Lebanon, initially “to provide an interposition force at agreed locations,” but later openly taking sides in that country’s civil war; and the 2011 intervention in Libya to provide airpower for regime change, just after the Obama repeatedly said this would not happen. “Saying one thing and doing another” has also characterized U.S. non-battlefield drone strikes from their introduction in November 2002.