Provisional patent applications are permitted, thus permitting a the filing of an inexpensive application to which priority can be claimed without reduction of the term of the patent. Your U.S. application is kept secret and never published by the U.S. patent office, until it is granted and you pay the issue fee. The U.S. patent office is service oriented. Applicants are treated like customers. Telephonic and personal interviews with Examiners are possible.
Appeals are possible.
Therefore, it is more likely that patent protection of some sort will be obtained. Filing requirements and requirements for a detailed disclosure are more stringent in the U.S. than in other countries. Once you have prepared the application in U.S. form, then it is a simple matter to file in the U.S. and in most other countries. Unity of invention requirements are less stringent than in Europe, enabling the possibility of one U.S. patent covering two or more inventions than would be defined under the European standard of unity. A significant advantage of filing in the U.S. first, is, if no further filings are made, a U.S. patent can provide protection for the inventor or licensee in ways which extend beyond the borders of the United States.