Although the U.S. is currently dependent on Russia for rocket engines, the country is now looking to end this relationship in favor of extending their contract with Elon Musk's SpaceX. However, some are warning that this route is unsafe.

Congress is aiming to end the use of the Russian RD-180 by 2019, but a panel commissioned by the U.S. Air Force is warning that this will not only cost taxpayers billions of dollars, it will compromise the use of the Atlas V, one of the superior rockets for military launches that is currently using the Russian RD-180.

Despite the panel's warnings, Congress believes that the use of the RD-180 makes the U.S. overly dependent on Russia and Vladimir Putin, allowing the country more control over launching timelines than Congress would like. They claim that this relationship is both an inconvenience and a national security threat.

"Vladimir Putin continues to hold our national security space launch capability in the palm of his hand through the Department's continued dependence on Russian rocket engines," U.S. Sen. John McCain said. "This is a national security threat, in addition to a moral outrage."

Currently, SpaceX is one of two aerospace companies that are qualified for military launches, along with the United Launch Alliance (ULA). They are the only alternatives to Russia's RD-180 at the moment, which is pressuring the two companies to compete with each other and thus far has stimulated numerous impressive developments in the field.

Given the developments pushed on by competition between SpaceX and ULA, the panel recommended that the U.S. continue to use the RD-180 and let these two companies continue competing with each other. They claim that this will allow for better management of any setbacks or engineering issues that could arise from the technologies that come from each company.

ULA is currently developing the Vulcan rocket, which has the potential to replace the Atlas V. The development is being conducted in conjunction with Jeff Bezos' Blue Origin, a privately funded American aerospace developer.

Prior to 2015, ULA had a monopoly on the industry, but now, recent advancements by SpaceX have given them competition, giving Russia's technology less and less value.