Is it a good idea for the public to be able to obtain concealed guns permits?

Many states allow the public, not just law enforcement, to carry concealed guns. Depending on the state, the person has to either p a written and practical test and/or attend a specified length of course. Although some states make it harder than it really should be. In addition, the person has to p a criminal background check, be a US citizen, and follow certain restictions once the permit is issued. For instance, not to carry one into an airport terminal, Federal court house, and to not be drinking and carrying. What do you think about this idea? Should all citizens be required to carry and know how to use the gun they carry (show profiency)? Would this help to deter or reduce crime? Does this fall under the Second Admendment?