In 1862, William B. Mumford was sentenced to death for removing an American flag. These days the rules aren't quite so extreme, but flying the Star-Spangled Banner upside down can be enough to spark outrage. So I imagine, then, if you were to kick over that stereotypical suburban picket fence, trample the patio lawn and hoist up a big Korean flag right after setting the Stars and Stripes on fire… well, it would be enough to cause a riot.
It's hard to deny that Homefront is trading on obvious shock value. The opening of the game bundles you onto a bus, probably off to some grim labour camp, and then forces you to watch two parents get executed via firing line while their now-orphaned child screams nearby. The occupying Korean force should be more careful: that's how Batmans get made.
Failing the Caped Crusader, I'm willing to bet the heavily-armed American resistance will probably cause its fair share of trouble. Kaos has clearly gone to great efforts in creating a chilling, believable and attention-grabbing vision of an occupied America in 2027. Even the opening scenes of the game are a far more competent portrayal of eroded American society than Modern Warfare 2's lifeless (though spectacular) Burger Town restaurant.
Sometimes the subject matter is particularly striking, and Kaos is insistent on having its America play similar roles to contemporary countries under foreign occupation. For instance, ragtag leader Boone and his gang of resistance fighters hide amongst civilian communities, knowingly (though, it must be said, not willingly) damning the nearby non-combatants to get caught in the crossfire from inevitable Korean retaliation.
This translates into things like a sequence where you defend a house from streaming waves of Koreans while a lone woman (who can't die) runs around with a wailing baby. If Kaos is going to park its heroes smack-bang in the middle of the suburbs, the chilling tone would be better served if the areas were more populated. How far the developer is willing to take its shocking subject matter remains to be seen, of course.
Kaos has made much of the claim that you're not playing through the campaign as Gary McSuperSoldier from the elite branch of the Ultramilitary, but it's clear from the opening level - where it's revealed your character, Robert Jacobs, is a pilot with extensive combat experience - that you're not simply playing as a regular Joe, either. But maybe that's for the best: I'm a normal civilian and, like all normal civilians, if you put a gun in my hands I'd collapse in terror and then go back to thinking about my favourite flavour of Doritos.