Excuse my ignorance, but is it legal to carry a handgun in the car in most US states? In Canada, we're lucky if we can use a rifle on the farm, and owning an handgun would be like trying to sneak out the door with baby jesus.
Concealed carry laws vary from state to state. I believe there is only one state (IL) that does not have some provision for concealed carry by private individuals.
A number of states have discretionary licensing, where concealed carry permits are issued at the discretion of some authority. That authority might be at the state level (e.g., the Attorney General in RI), at the county level (e.g., a county judge in NY), or at the local level (e.g., chief of police in MA). In some discretionary states like MD, it is almost impossible to get a concealed carry permit. In other states like MA, it varies from almost impossible to easy, depending upon where you live in the state.
A large number of states have so-called shall-issue concealed carry permits. In those states, the authority MUST issue the permit provided the applicant meets the statutory requirements -- no discretion is allowed. The reason for the spread of this type of law is the almost universal abuse of discretionary licensing wherever it has been enacted. States with shall issue permitting include FL, TX, IN, ME, NH, etc.
A few states don't require a license to carry concealed - VT, AK, and I think AZ just went this route.
That said, even if you have a license to carry concealed, many states have laws that place certain areas off limits. In MA, schools are off limits. In some states, any restaurant that serves alcohol is off limits, even if you aren't drinking or sitting in the bar area. And federal property is generally off limits as well, though National Parks are no longer off limits (but the buildings on National Parks are off limits).
And while a drivers license issued by any state is valid in any other state in the Union, a concealed carry permit may or my not be honored by another state. It's a crazy quilt of concealed carry laws here in the States.
Oh, and to add to the confusion, in some states it is legal to have a loaded handgun in your car even if you don't have a concealed carry permit. In other states, like NH, you must have a concealed carry permit to have a loaded gun in your car.