The base isn't interested in Iraq. The base is for Bush. If Bush said tomorrow, we're leaving in two months, there would be no revolt.
It's hard for non-lizard brain people to see how they could pivot on a dime like that, but noted Bush basers like Glenn Reynolds spent years arguing against more troops in Iraq then immediately went to arguing the opposite as soon as Dear Leader said it was a good idea.
So, yeah, Grover's probably right. They'd just need to create some fake political event to allow them to declare victory and go home.
But Bush won't do it. And the 30 percenters are happy to stay in Iraq just as they'd be happy to leave. Whatever Dear Leader says is fine with them.