No, to say that marijuana is a dangerous drug is not crazy. Many people have "mellowed out" toward marijuana use and do not think it as bad as alcohol is. It is a schedule I drug according to the United States Drug Enforcement Administration.
I had problems with marijuana soon after I started smoking it when I was in high school. My commitment to schoolwork diminished, my grades fell, I lost friends, I slept more, I had concentration problems, and was caught and ended up in drug rehabilitation. I recovered from it only to go back to it a year and a half later. After then, it gave me the same problems as before, but that time around, things were even worse. I was able to quit on my own once I noticed I was having problems again because of the marijuana.
I may have been addicted to it when I was on it, or it may have just been a social thing for me. Either way, using marijuana set me back in life and I thank God that I was able to quit.