The industry has been waging a fierce campaign to kill the “Basel endgame” proposal, which overhauls how banks must calculate their loss-absorbing capital, and as regulators roll out fair lending and fee cap regulations, among other rules.

The CEOs hoped to use the hearing as an opportunity to convince key moderate Democratic senators that the Basel rule, which is being led by the Federal Reserve, could stifle lending, hurting small businesses and consumers.

It quickly became a battle of narratives, with many Democrats casting skepticism on the industry’s complaints and accusing them of over-emphasizing the risks, while Republicans and the CEOs stressed the potential adverse impact on a range of products and services, from green lending, commodities hedging, and pension plan services, to Treasury market liquidity.

“If enacted as drafted, this proposal will fundamentally alter the U.S. economy in ways that the Federal Reserve has not studied or contemplated,” Dimon, CEO of the country’s largest lender JPMorgan, said in his prepared testimony.