“Quite a few of my members were expressing concern and nervousness,” said Michael Elliott, executive director of the Colorado Marijuana Industry Group. “But I’m not sure we could have expected much more than we just heard. Even the president, who came out saying that marijuana is no more dangerous as alcohol, is also on the record as being against legalization.”

States that have legalized or are considering legalizing recreational marijuana use butted heads continually with Attorney General Eric H. Holder Jr., who refused to relax stricter federal laws against pot use. Judging from this week’s performance, the fight won’t end when Mr. Holder leaves.

A federal prosecutor in New York, Ms. Lynch told the Senate Committee on the Judiciary she disagreed with the president’s no-big-deal take on pot, saying, “I certainly don’t hold that view and don’t agree with that view of marijuana as a substance.”

“I think the president was speaking from his personal experience and personal opinion, neither of which I’m able to share,” Ms. Lynch said. “But I can tell you that not only do I not support the legalization of marijuana, it is not the position of the Department of Justice currently to support the legalization. Nor would it be the position should I become confirmed as attorney general.”