Rep. John Dingell (D-Mich.) didn't give his friend Al GoreAl GoreOvernight Energy: Exxon sues feds over M fine | Deputy Interior pick advances | Oil concerns hold up Russia sanctions push Gore: Progressive ideas 'gaining ground' among Democrats Gore: Trump prompting 'biggest upsurge' of climate activism ever MORE a free pass when he questioned the former VP during his House testimony today.

"Cap and trade is a tax, and it's a great big one," Dingell said.

He pushed Gore to explain why adopting cap-and-trade wouldn't lead to the same failures Europe encountered with such policies. And he pushed the former VP to explain why America should make such a sacrifice when other big polluters are not.

"They're going to skin us," Dingell said of industrial polluters like China. "How do we protect our people?" he added.

Dingell is the former chairman of the House Energy and Commerce committee, a subcommittee of which Gore was appearing before today. Dingell was replaced by Rep. Henry Waxman (D-Calif.), who is sponsoring the legislation under consideration.

The Michigan Democrat said he wants to make sure energy-intensive industries are allowed to transition into any new regulatory scheme.