Comedy Central
Stewart, hosting "The Daily Show," was referring to Bieber's egg-throwing incident that led to a raid of his home.
"Throwing away, for no reason whatsoever, a tremendous opportunity because of immaturity and a lack of self-control," Stewart said.
The consideration of new sanctions in Congress comes despite an interim agreement reached in Geneva in November. The legislation being supported by 59 bipartisan senators proposes sanctions in the event that Iran breaches the terms of the interim agreement - or if world powers fail to come to a comprehensive agreement regarding Iran's nuclear energy program.
President Barack Obama has said he'll veto any new sanctions legislation. During a meeting with Senate Democrats on Wednesday night, Obama reportedly pushed them to hold off for the time being.
Stewart wasn't surprised that Republicans would line up to impose new sanctions - "they would line up to oppose Obama on the Orgasms Cure Cancer Act." But he was particularly critical of the 16 Democrats co-sponsoring the legislation in the Senate.
Here's the full clip, courtesy of Comedy Central:
The Daily Show
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