Oh, no. Russia is mad at us again.

Russian Deputy Prime Minister Dmitry Rogozin has vowed to punish the U.S. for imposing sanctions over his nation's invasion of Crimea. After being included on the list of targets for sanctions, Rogozin released rapid-fire statements last month in which he:

objected to the Pentagon using Russian equipment to launch U.S. military satellites

promised to block the sale of Russian RD-180 rocket engines to U.S. space launch company United Launch Alliance (ULA)

threatened to terminate "cooperation" with the United States on the International Space Station -- presumably by denying U.S. astronauts rides to the ISS aboard Russian rockets

mocked America's too-early termination of its space shuttle program, quipping: "I propose that the United States delivers its astronauts to the ISS with the help of a trampoline."

So I guess you could say that relations between the United States and Russia are not particularly strong right now. And with the U.S. lacking a single operating spacecraft certified for manned spaceflight, this poses something of a problem.

But fear not. The U.S. Air Force is searching for a solution.

An end to outsourcing national security

Commenting on the impasse, Air Force Undersecretary Eric Fanning said it's time for the U.S. to "explore ways to mitigate our reliance on the RD-180." (That's the Russian engine that ULA partners Boeing (NYSE:BA) and Lockheed Martin (NYSE:LMT) use to power the core stage of their Atlas V rocket.) Responding to Rogozin's threats, the Pentagon set up a committee under retired Air Force Maj. Gen. Howard Mitchell to recommend options to deal with the RD-180 issue. It quickly came up with the obvious one.

We need a new rocket engine.

One made in the U.S. of A.

Defense Secretary Chuck Hagel agrees. In recent testimony before the House Appropriations Committee, Hagel said, "I don't think there's any question" but that the U.S. needs to begin building its own heavy rocket engines.

Why? Because the Pentagon says our dwindling supply of RD-180 rocket engines means that in just 22 months, space launches will become "not supportable."

How to fix the problem

So how will we ensure America's continued access to space? Fanning believes developing an alternate engine via a "public-private partnership" between the Air Force and private industry may be the way to go. The good news is that several American companies -- publicly traded entities that you can invest in -- are already hard at work developing alternatives to the RD-180.

The better news is that you really only need to know three of them.

Alliant Techsystems (NYSE: ATK)

Space-tech specialist Alliant builds the solid-fuel rocket boosters that help lift America's rockets into space. Alliant's boosters were used on the space shuttles, and have been chosen to power NASA's shuttle replacement, the "space launch system," or SLS. Alliant was also chosen as one of a handful of companies working on ways to improve the affordability, reliability, and performance of our boosters, for use on the SLS as a new "advanced booster."

NASA expects the improved design to generate "more thrust than any existing U.S. liquid- or solid-fueled boosters," enabling the launch of up to 143-ton payloads aboard the SLS. The space agency plans to execute the first SLS test flight as early as 2017, sending an unmanned spacecraft into lunar orbit.

Orbital Sciences (NYSE:OA)

In 2010, NASA named Orbital as one of several space tech companies permitted to compete for development work on a new heavy-lift rocket engine to power the SLS. The company's biggest rocket engine today is the Antares, used to lift Cygnus unmanned spacecraft to the ISS on resupply missions. Antares is only capable of lifting payloads of 5,000 kilograms, however. That's barely a quarter of what's needed to get even an Atlas V launcher into low-earth orbit.

Orbital is due to merge with Alliant later this year, combining two strong players in space tech into one -- and potentially accelerating the rocket development efforts of each.

GenCorp (NYSE:AJRD)

Arguably the company to beat in this race, rocket tech shop GenCorp has assembled a rocket-science powerhouse by combining its own Aerojet operation with what used to be United Technologies' Rocketdyne. The new Aerojet Rocketdyne manufactures the RS-25 rocket engine, which powered space shuttles for 30 years. In fact, GenCorp now owns an entire family of proven, half-built, and still-being-worked-out rocket engines, from the RS-25 to the RL-10 to the new RL-60 and J-2X (designed to power the upper stage of SLS launches).

It's also possible (GenCorp did not respond to a request for comment) that GenCorp could build the RD-180 itself. According to some media reports, United Technologies purchased engineering design plans to build the RD-180 from the engine's maker, Russian engineering company Energomash. If those plans, and the rights to build the engine, passed from United Tech to GenCorp when it acquired Rocketdyne, then GenCorp could be in a position to begin manufacturing RD-180s on its own, should Russia follow through on threats to embargo future RD-180 sales.

Foolish final thought

Or not. Domestic manufacture of RD-180s may be a pipe dream. But even if it is, one thing's for sure: Russia's threat to cut off our RD-180 supply has upset the comfortable apple cart upon which ULA was lounging. Now there's a mad scramble of competing companies offering competing ideas for how to regain U.S. space launch independence.

Innovation has been unleashed, and going forward prices will fall, and dependence on Russia will vanish.