Is Kraken available in the US?

Could you please clarify if Kraken, the popular cryptocurrency exchange, is indeed accessible and operational within the borders of the United States? I'm particularly interested in understanding if US residents and citizens have the ability to utilize its services for buying, selling, and trading various digital currencies. Is there any regulatory framework or restrictions in place that might impact its availability or functionality for those residing in the US? Additionally, could you provide any insights into any potential challenges or limitations that US users might encounter while navigating Kraken's platform?