It wasn't just Gagarin either...in 1963 Valentina Tereshkova became the first woman in space, followed by the first three man space crew, followed by the first space walk.
These accomplishments were eventually eclipsed by the first successful moon landing but remain as empirical evidence of 20th century Soviet technical prowess.
The fact the United States still relies on Russian rocket technology in the 21st century is simply more empirical evidence that defies the stereotype this author attempts to portray.
The decision to use the RD-180 for the Atlas V launch vehicle is a result of post-cold war cooperation between U.S. businesses and the Russian defense industry. The RD-180 relationship was urged by the U.S. government as a means of preventing Russian military technology from proliferating. The RD-180 was jointly developed by U.S. and Russian Defense Industries to provide the Atlas V with a technologically advanced and reliable engine. Since then, the Atlas V product has provided enormous value and mission assurance for ULA customers.
http://www.ulalaunch.com/faqs-rd-180.aspx
https://en.wikipedia.org/wiki/RD-180
The reason to use the Russian produced rocket engine was not only to prevent proliferation, but as well financial. The production cost in Russia was, and is, much lower than in the US: The added cost for launches would be over $2 billion,
http://www.forbes.com/sites/lorenthompson/2016/05/23/banning-russian-rocket-engines-will-increase-costs-and-risks/