RD180 Rocket Engines

RD180 is the engine that powers the United Launch Alliance's (ULA) Atlas V heavy lift booster rocket.  One little problem has emerged lately, the RD180 is made in Russia.  Just how a Russian built engine became the main engine of an American booster is a little hard to tell, now.  Tracks are being covered even as I write this.  At a guess, the Russians were low bidders, and someone decided that they were a reliable supplier. 
  Anyhow, after the late unpleasantness in Ukraine,  the Americans started huffing and puffing about "sanctions" and the Russians retaliated by threatening to cut off the supply of RD180 engines.  Which would put the Atlas V and ULA out of business.
   So, ULA is talking about having Blue Origin, a secretive Seattle based rocket company, started by Jeff Bezos the Amazon.com zillionaire, design and build an RD180 replacement engine right in Seattle.  Dubbed BE-4, the engine would burn compressed natural gas and LOX and produce  550,000 pounds of thrust.  Blue Origin has been doing some design work on BE-4 using in house (Jeff Bezos) funding.  ULA has signed a deal to provide more funding.  Target date for first flight is 2018, four years from now. 
   We have a stockpile of Russian built RD180 engines good for two years.  I guess they are hoping that the Russians will sell us another couple of years worth of engines.  Or, that with a LOT of more money the BE-4 could be rushed into production.
  Or, we could drop ULA and Atlas V and use the Space-X Falcon 9 booster rocket which has roughly the same performance as Atlas V.