Responsibility to whom? This is a really tricky issue.
If responsibility means simply "knowingly contributing to the problem despite having other options available" then indeed we can claim that large segments of the US population, including the working class, are "responsible," albeit partially, for the actions or lack thereof of the US state. That partial responsibility lies in their choices that include - sending a steady supply of fascist trolls like Jesse Helms, Tom DeLay, Newt Gingrich, George Bush and scores others that used to be known as boll weevil Democrats while rejecting alternative political candidates (cf. countless unsuccessful efforts to unseat Jesse Helms); - supporting christo-fascist organizations, from the KKK to the NRA to Southern Baptists and to terrorist anti-abortion outfits, while rejecting other alternatives that could advance their interests (such as labor unions, empowerment organizations such as ACORN, environmental protection organizations etc.); - volunteering as mercenaries in the US armed forces which are clearly and obviously used for offensive rather than defensive purposes; - willingly participating in vigilante actions, from "border protection" to lynching mobs targeting perceived enemies of the US state and order.
Of course it is unjustified to say that any particular social class is "responsible" for that, because not all members of any particular class make such choices, but it is fair to say that certain socio-demographic groups are more likely than others to make these choices (e.g. Southerners more likely than Northerners, whites more likely than blacks, men more likely than women, suburbanites more likely than urbanites, and so on). We can, of course, define groups in a more refined way, e.g. "white male Southern suburbanites" which results in increased likelihoods of making these choices.
If "responsible" means also "accountable for their choices" - this automatically brings the question "to whom?" We can easily dismiss meaningless abstractions such as "god" "history" "the people" etc. - but naming a more empirically identifiable entities is not that easy at all. What would they be - self-styled revolutionary tribunal or a vanguard party? How about "citizens' militia" "jihad" or kindred group seeking to avenge 'wrongdoings' by this or that infidel group? Courts of justice - either domestic or international? They have a rather poor record of dealing with collective responsibility so they usually end up with punishing token scapegoats i.e. leaders. It does not mean that the leaders are innocent or do not deserve the treatment they receive. It means that these leaders would be unable to function and did their heinous deeds without the active or tacit support of numerous followers and enablers who simply go unpunished.
So the bottom line is that large segments of the US population are "responsible" i.e. instrumental in the actions of the US state, they are "little Eichmans" or "Hitler's willing executioners" to use the popular catch phrases - more so than, say, the Soviets or the Chinese, who do not have the choices that the US-sers do. But that statement does not provide much guidance what to do about it - ban them form public life? seek collective revenge? Given these choices, ridiculing some iconic representations of the groups of people that make those choices seems fairly innocuous, indeed.
Wojtek