Out of and quickly back into Iraq, the Pentagon and its officials have talked about the new ISIS war with barely restrained glee as another chance to keep pushing Congress for bigger budgets, and for “emergency” war funding every single year.

Retired Marine Gen. John Allen, who has become President Obama’s special ambassador for the war, going around the world selling it to potential allies, today predicted the conflict would be much longer than anyone imagines, saying it “will likely take a generation or more.”

Citing his four decades in the Marines, Allen insists ISIS is the most brutal group ever, and claimed they are a threat to “the progress of humanity” if not defeated militarily. Which, again, he says is going to take “a generation or more.”

The American publicly is likely not up for another protracted, nation-bankrupting conflict, particularly since they’ve already got one ongoing in Afghanistan and just freshly got extricated from the last one in Iraq. Polls show war weariness already growing among voters nine months into the new war, with 61% saying the war is going badly, and 29% saying it’s going “very badly.”

That’s a surprising level of skepticism for this early in a war, particularly with the administration loudly insisting, every chance they get, that they are “winning” the war. The public is clearly not buying it, and that’s going to be a problem for the pro-war factions of both parties as months extend into years, let alone “generations.”

To the extent officials attempted to sell the American public on the ISIS war at all, it was couched as an extremely limited conflict, both in scope and timescale. The Pentagon has since escalated their involvement countless times, seemingly only making things worse with each escalation, and is now making it plain that what was supposed to be a quick intervention to shift the momentum in favor of the Iraqi military is actually going to be an endless war of attrition aimed at destroying the de facto caliphate.