Can US citizens use Kraken Exchange?

Could you please clarify whether US citizens are allowed to utilize the Kraken Exchange platform for their cryptocurrency transactions? Are there any specific regulations or restrictions in place that may hinder their access or limit their trading activities on the platform? Additionally, is there a need for any specific verification processes or documentation that US-based users must comply with in order to trade on Kraken Exchange? It would be greatly appreciated if you could provide a concise yet comprehensive overview of the situation for US citizens looking to engage with Kraken Exchange.