Maybe, maybe not. As mentioned in a previous comment, prison is primarily used as a punishment here not as much for protection of general society. In a country founded on the principal of various innate freedoms taking away someone's freedom seems the ultimate punishment. Fines = Taking your means to buy what you want = Taking your freedom to acquire. Revocation of licenses (drivers, professional) take away your freedom to legally perform certain activities. Prison, and the associated probation/parole system, go steps farther by explicitly removing all, or almost all, but your barest freedoms. Execution takes your final freedom (Life) away.
Personally I think a 10 year sentence is pretty excessive. Your average privileged American is pretty shell shocked by even small amounts of time behind bars. Months to a couple years is enough of a penalty to reform the vast majority. Those that don't fit that mold become repeat offenders where the penalties deservedly go up. Extreme example: I could walk out of my office right now and gun down someone in cold blood and I wouldn't end up with 10 years. I don't disagree at all with Prison being the style of punishment but I find the duration to be excessive and honestly for first offense pending aggravating circumstances a friendly prosecutor would probably be happy with a number of years of probation in-lieu of. The whole concept of "Trying to send a message" is an abortion of our legal system and should be weeded out with appropriate diligence.
PS: The whole misunderstood argument is similarly BS. I break laws all the time and when I get caught I pay the price. I am truly understood by only myself but that is no argument that I shouldn't be judged based on the same laws my fellow citizens are. I instead work to change those laws I disagree with so I can spread my own understanding.