Aggressive Drivers

Why do drivers think that after they get their licenses they think they can drive however they want? I drive an 18-wheeler for a living and during the day I have at least 4 or 5 people change lanes with only 2-3 feet between them and my rig. Do these people have a deathwish or do they do not know it takes about 1 truck length per 7 mph to stop safely? I wish I knew. I have yet to have a wreck in my rig (knock on wood) and hope I never do. I also hope I never have a wreck that may be fatal. I have talked to other drivers that have been in a fatality accident and they say that it is very hard to get over it. Please tell everyone you know to not do this. Please pass this on. Not only that the more aggressive you drive the more gas you use. Another thing I deal with is people not yielding like they are supposed to. Or when I yield they change lanes to keep truckers from merging into traffic safely. I have had to merge into INTERSTATE TRAFFIC FROM A STANDSTILL! This will also get a person killed. Please drive courteously and safely. I do and plan on driving that way from now on. I don't want to be the driver that has to deal with a fatality because of someone's stupidity. Now I also realize that not all truckers drive safely. But because you never know, please give ALL of us truckers plenty of room to do our jobs safely. Thank you in advance.