Is Bitfinex available in the US?

I'm interested in exploring the world of cryptocurrency and have come across Bitfinex as a potential trading platform. However, I'm a bit confused about its availability in the United States. Could you please clarify if Bitfinex is operational in the US? If so, are there any specific regulations or restrictions that US users need to be aware of? Additionally, I'd like to know if there are any alternative platforms that offer similar services but are more suitable for US-based users. Thank you for your time and assistance.