Nothing has been decided on the extent or scope – or the very existence – of the cap and trade program at the heart of any energy and climate bill moving through the Senate this summer. But industry-wide cap and trade does look unrealistic for now. The White House has already backpedaled to a power-plant-only approach.

President Barack Obama’s meeting next Wednesday with senators to get energy legislation back on track will likely include discussing a climate change component that caps carbon emissions only from electric utilities, White House Chief of Staff Rahm Emanuel said today in an interview.

“The idea of a ‘utilities only’ [approach] will also be welcomed,” he said, emphasizing that “a wide range of ideas will be discussed.”

Honestly, they’ll be lucky to get that. Senate Democrats are openly mocking John Kerry for his advocacy of a carbon cap, so obviously Kerry-Lieberman isn’t about to go anywhere. There’s some glimmers of support among a few Senate Republicans for a utility-only approach, which would cover a healthy percentage – over half – of all emissions.

This has not impressed environmental advocates, who favor an industry-wide approach. But there’s no game plan on how to fight back.

“I’ve been disappointed,” said Kyle Ash, a lobbyist for the activist group Greenpeace. “This really is just a slightly better version of what I would have expected a Republican White House to do if there was a disaster like this in the Gulf.”

A number of liberals also turned their fire on long-established environmental groups that remain closely allied with the administration, including the Sierra Club. The group’s executive director, Michael Brune—prompted by liberal blogger Jane Hamsher, who said the group was playing “an inside game” with the White House—shot back on the Huffington Post website. He noted how he and his colleagues had mobilized to block expansions of coal mining and oil drilling.

Still, Mr. Brune conceded that he has seen “reluctance by smart campaigners and organizations to criticize the president, primarily because those people or groups support much of what the administration is trying to do.”

This is a real split, and the lack of a united front harms efforts at pressure. This has been true of the entire climate debate, which is why it has featured an unimpeded collapse from industry-wide, 100% auctioned cap and trade down to the morsels we see now.

The lack of unity of effort, inside and outside of Congress, leads to weak solutions, frustration, and confusion about goals. That’s what the Democratic agenda looks like here in mid-2010.

UPDATE: David Roberts considers the utility-only carbon cap approach, finds it preferable to an energy-only bill, affecting about 1/2 of total emissions reductions in the energy sector. He adds that utility-only could work, but must be accompanied by strong clean energy provisions. This is basically the problem with this haphazard approach without a unified base of support. Too many moving parts, nobody knows what to advocate for.

UPDATE: An interesting take from Michael Levi on this, including this very smart observation: “It has been very tough to tie cap-and-trade to public outrage over the oil spill. A cap-and-trade system that deliberately does nothing about oil will be even harder to sell from that angle.” There would be some particular provisions in the bill related to the Gulf disaster, but there is a certain insanity to this.