It is not a case of being advisable, you definitely need a visa for China if you are flying directly to and from PEK to the US. They won't let you board your flight from the US to PEK if you dont have a visa for China. The only way you can void getting a visa is if you are flying from country A into China, and onto country B. They have a concept of transit-without-visa (TWOV).

China 24, 72, and 144 hour Transit Without Visa ("TWOV") rules master thread