That's all the more reason not to dismiss a political movement that is not "really anti-capitalist" or suggest that a movement that is not "really anti-capitalist" is or will be necessarily anti-Semitic. That's like preemptive sectarianism, i.e., sectarianism against a movement that doesn't even exist.
While a rise of economic populism in the USA is highly unlikely at this point, it is not totally unthinkable. Suppose personal consumer debts and mortgages become finally unbearable sometime in the near future. Then, Americans might once again begin to think about the question of finance. If they do, their first thoughts about it will be probably very wrong, surely not "really anti-capitalist." Leftists will have to think about what to do with those first thoughts.
Beyond the USA, too, the notion that a state or movement that is not "really anti-capitalist" -- whatever being "really anti-capitalist" means -- is not worth defending is a self-defeating and self-marginalizing one. Thankfully, not many hold such a notion in Latin America, though there are some who do. -- Yoshie <http://montages.blogspot.com/> <http://mrzine.org> <http://monthlyreview.org/>