Yes - and millions of Americans use pot and don't commit mass murder.
Its best to understand that the biochemistry of human thought is not understood. The brain is 90% phospholipids. Just how those lipids churn up there to make the higher intellectual functions of humans possible is the great scientific quest of the new millennium. Almost all medications, legal and illegal, used to modify or “treat” human behavior patterns is at best at its core Edisonian empiricism. Some chemicals “work” and other not only don’t but have some unpleasant side effects. Marijuana defenders can say what they want to justify and placate. However if you merely review what has happened to Western civilization over the past fifty years, it does not take a CDC genius to note that the decline closely parallels the extent that drug use has become common in the population. Simply not wise to ignore or trivialize if your young loved ones habitually use marijuana.