Is Kraken legit in the USA?

I've been hearing a lot about cryptocurrency exchanges, and Kraken seems to be one of the more popular ones. However, given the volatile nature of this industry and the numerous scams out there, I'm wondering: Is Kraken actually legit in the USA? Are they registered and compliant with all relevant financial regulations? Are their security measures robust enough to protect my investments? And what about their customer service? Are they responsive and helpful in resolving any issues I might encounter? Clarifying these points would help me make a more informed decision before diving into the world of cryptocurrency trading.