In this paper, the author argues that the tenuous relationship between the US and Russia regarding ballistic missile proliferation and defense systems is in jeopardy. As US ballistic missile defense expands, Russia’s nuclear deterrent weakens. This may result in Russia finding new capabilities to circumvent US defense systems to maintain what they believe to be a balance between the countries. Technological advances and further expansion on both sides threaten stability and put future arms control agreements at risk. [Shawn A. Russell / 2020 / 80 pages / ISSN 2687-7260 / AU Press Code: WF-80]