Israel royally screwed up and the US should be completely pissed off. Like any technology out there, it is to a competitors benefit to acquire one's technology. Granted you cannot reverse engineer it entirely, but here are the benefits. 1) Much cheaper than investing your own R&D resources for tech that already exists. 2) It advances your development by years by acquiring them. 3) Most importantly, it gives Russia an insight to the pros and cons of Israel's/USA's technology and how to better exploit them. This is like Bill Clinton selling advanced guiding technology to China's aerospace program which in turn is dual purposed for intercontinental ballistic missiles. Oops!
Austria's far-right leader Strache blames U.S., NATO for migrant crisis (Reuters)
from the article: Israel signs $400 million deal to sell spy drones to Russia