Quite the accusation. If he could prove collusion, I would be in favor of some sort of punative measures. Without that, however, it is wrong to confiscate corporate profits based on market forces outside of their control. This is especially true if the government bears a lot of responsibility of this mess due to past pacification of despot regimes, over regulation, and a failure to exploit domestic resources.
Well, OPEC does collude. That's why it was formed, and its members make no bones about it. Members get together in Vienna and agree how much oil each will supply to the market.
It is absurd to assert that OPEC members can be subject to US antitrust laws. Its members are sovereign nations, not companies doing business in the US. Unlike the US, the oil in OPEC member states is owned by the government, not private oil companies.