We can assume that this adversary was immediately made aware of the 1947 Roswell crash and even other extraterrestrial crashes before Roswell.
However it was Roswell that seemed to push government leaders and those industrialists, bankers and European royalty that pulled the financial strings of government, into action to protect their self-interest and to exploit special access to alien technologies. Ben Rich¹, former head of the Lockheed Skunkworks, was not joking when he said: