The claim is made that Russia’s Security Council is considering a ban on selling RD-180’s to the US. This would kill the Atlas V, since the US does not have a second source for the engine. Back in the 1990’s there were plans to produce the RD-180 in the US, but the decision was made to simply buy them from Russia.
If this is true and comes to pass, it will be yet another in a long, dreary line of events that point out why international ventures between nations – in particular ventures where each nation produces something vital that the other nation does not – that really don’t like each other is a fundamentally bad idea. It will also point out the importance of having in-house capabilities, such as designing and building rocket engines.
Boeing, I imagine, won’t be too upset by this, as the Delta IV will be happy to pick up the slack from Atlas V. However, that will put US space launch in a bit of a bind, as we’d be restricted to the single heavy launcher. At least unless and until the SpaceX Falcon 9 Heavy becomes available.