As public support for legalizing marijuana rises and Americans get used to the reality that two states have already taken that step, signs of pot tolerance are mutiplying. Here are three recent ones that are pretty remarkable in light of marijuana's long history as a taboo substance:

1. Last month Pat Roberts, the 78-year-old Republican senator from Kansas, was asked about marijuana legalization during a debate with Greg Orman, the independent candidate who is beating him in recent polls. Here is Roberts' reply:

That's not a federal issue. That's a state issue. If you want to get a Rocky Mountain high, go west. That should be for the Kansas legislature and the governor to decide, not federally.

Roberts, who has been a member of Congress since the beginning of the Reagan administration, is not advocating legalization. But his willingness to let states go their own way on this issue is striking coming from a Republican senator with an American Conservative Union rating of 86, especially since he is fighting for re-election in state that is not known for its pot friendliness.

2. A few weeks after Roberts endorsed marijuana federalism, Attorney General Eric Holder suggested that marijuana does not belong on Schedule I of the Controlled Substances Act, which is supposedly reserved for drugs with a "high potential for abuse" that have "no currently accepted medical use" and are so dangerous that they cannot be used safely, even under a doctor's supervision. Here is the relevant exchange from Holder's interview with Katie Couric of Yahoo News:

Couric: At the federal level, marijuana is still classified in the same category as heroin. In your view, should that change? Holder: I think it's certainly a question that we need to ask ourselves—whether or not marijuana is as serious a drug as is heroin, especially given what we've seen recently with regard to heroin, the progression of people using opioids to heroin use, the spread and the destruction that heroin has perpetrated all around our country, and to see, by contrast, what the impact is of marijuana use. Now, it can be destructive, you know, if used in certain ways. But the question of whether or not they should be in the same category is something that I think we need to ask ourselves, and use science as the basis for making that determination.

Since Holder, as attorney general, has the power to reclassify marijuana without new legislation from Congress, it would have been nice if he had talked about this a little more before he was on his way out the door. Still, his willingness to question marijuana's Schedule I status—something no sitting attorney general has ever done before, as far as I know—reflects a dramatic change in the climate of public opinion. Contrast Holder's remarks with the more traditional position taken by Michele Leonhart, the head of the Drug Enforcement Administration, who adamantly refuses to concede that marijuana might be less dangerous than other drugs.

3. Last week on Everyday, the mid-morning show on KDVR, the Fox affiliate in Denver, co-hosts Chris Parente and Kathy J. were discussing the best bargains at Trader Joe's with "money maven" Sandra Hanna when they casually touched on the hazards of shopping while stoned:

Hanna: Now, when you're in the cheese aisle— Parente: Which Chris Kattan said you should do stoned. Kathy J.: Do stoned. Get stoned and go in the cheese aisle. Apparently, it's awesome. Hanna: It's not a Smart Cookie move to go shopping stoned ever. That's a general rule of thumb. Parente: You'll spend a lot of money. Hanna: A lot of money.

In some ways, this jokey exchange is especially revealing, reflecting the sort of cultural shift that occurs when an intoxicant moves from illicit to licit. It seems likely that local TV hosts in Denver would be less inclined to allude to their own experiences with marijuana on the air if Colorado voters had not approved Amendment 64.

[Thanks to Tom Angell, Paul Armentano, and Robert Woolley for the links.]