There are three ways to obtain a patent in the United States:
(1) Apply directly;
(2) The Paris Convention, and
（3）PCT。

Each of the three approaches has its advantages and disadvantages:
(1) "To apply directly" requires applying for confidential examination in China first, there is a risk that China family patents will be invalid in the future if the confidential examination is neglected.

In addition, "directly to apply" require  to find patent engineers who can directly draft the US patent application documents, which is quite difficult, but once you find the well-versed engineers with the ability to draft both Chinese and American patent application specifications, it will do more with less.

(2)The Paris Convention means that an invention or utility model is firstly filed in China,then, within 12 months,claim China priority, translat and rewrite into US patent application documents and submitto the US Patent Office.

 It should be noted that because the US patent system is different from the China patent system, there will be big problems if China patent application documents are directly and literally translated into English.

The most common issue is that the claiming structures are different. If it is not rewritten, the translated claims will be rejected by the Examiner. At least, it will waste the office action response cost, and at worst, the patent application cannot be granted.

(3)PCT approach, refers to the international patent application to enter the national stage, is currently a common way for many Chinese applicants,
the advantage of the PCT approach is that through the international retrieval report, the applicant can know whether there is  prospect of being granted for patent, and there is a priority period of 30 months beforing entering the national state. However, the disadvantage is also obvious, that is, when entering the national stage of the United States, it has strict literal translation requirements based on the PCT publication document

The three approaches, from the perspective of protection, the best is (1) and the worst is (3).