The rollout of Obamacare has been "absolutely chaotic," said Tommy Thompson, who served as U.S. Health and Human Services secretary under George W. Bush. But worse, he added, the new law is flawed and needs dramatic changes.
"It's actuarially unsound," the former Republican governor of Wisconsin said on CNBC's "Squawk Box" on Tuesday. "If you don't have the healthy young people involved, ... Obamacare cannot function. It's going to require a huge infusion of tax dollars or huge cuts."
One of the cornerstones of the new health-care law is that healthy young people will pay for medical insurance that they use less frequently than the elderly or the chronically ill.
But, Thompson said, from the view of a healthy young person, they may ask: "''Why do I want to do that?''"
Under Obamacare, most Americans have to buy insurance or face a tax penalty.
(Read more: Officials werewarned about Obamacare site woes NYT)