Yes that particular Mercury flight was suborbital, but it did test the reentry system and heat shields. We were in no way behind the Soviet Union in developing our space technology in 1961. It's just that the Soviets were willing to take greater risks with their personnel. The statement I quote said that our reentry systems were not perfected until several years later which is not true. Both Allan Sheppard and Gus Grissom successfully reentered the atmosphere in 1961, and the four manned orbital Mercury flights also successfully reentered the atmosphere.
Surely you jest. Ask John Glenn if his orbit around the Earth was real.