If you're a non U.S. corporate group and you're looking to expand operations into the U.S., generally the first step is to form a separate legal entity within the U.S. For example, you can form a Delaware C corporation which is 100% owned by your non-U.S. parent company. In order to protect the assets of your parent company and other operating subsidiaries, the U.S. based corporation must follow all of the required corporate formalities. You'll need to adequately capitalize the Delaware corporation, perform all annual filings and required tax returns, maintain adequate records of corporate decisions, etc. It's also recommended that the Corporation maintain adequate liability insurance coverage for the business operations, which would vary depending upon the nature of your business and the types of risks associated with your activities.

Thank you for your great question. It turns out that I was exploring a similar question with my lawyer in Alberta, Canada. Best business practice advice was to hire a USA lawyer within the State your are intending to do business. Many larger law firms in Canada for example can refer to other firms in the USA. Also, there may be a level of firm-to-firm coordination for the business. Best regards with your situation.