Mr. Kavanaugh is representing a faction of people in Arizona who really believe that pot is the devil's spawn and that any softening of drug laws will result in chaos. He- and they- are wrong, but it's essential to keep in mind that this is what they really believe.
People like this also believe- or did until very recently- that blacks should not have civil rights (Arkansas Governer Orval Faubus was a Republican), the alcohol and tobacco should be outlawed as well as all the current crop of drugs, that women do not need equal rights and have no place in the workplace, that workers don't need wage and job protections from their greedy and selfish employers (Rep. Paul Ryan), that consumers don't need protections (remember all the ballyhoo over Elizabeth Warren's appointment to The Consumer Protection Agency), that the environment is immune to anything and everything humans might want to do to it, that Wall Street can be trusted to police itself (so the Bush 43 administration cut the SEC's funding by 2/3... wonder if that had anything to do with the economy melting down over massive systemic financial fraud), that the constitution should only protect certain rights contained within as opposed to all of them- and then only for a certain minority- and that poor people don't count, have no need to vote- and should still pay most of the taxes.
Sure, when taken together, it sounds ridiculous. But these people are out there, make no mistake- I know, one of them lives next door to me. It is up to us to continue the fight for our rights and freedoms, because there will always be some dumbass head-in-the-sand types who think that trading away freedom for security is some kind of bargain.