Not a deterrent   In the previous version of this article the R was referred to as the first truly credible rocketbased nuclear deterrent in the Soviet arsenal  This is inaccurate  the long response time and unprotected launch facilities meant that the R was a firststrike weapon only as was its counterpart the Atlas because in case of a surprise first strike by the US all these missiles would have been blown to bits before they could even be fueled for launch  Ive changed the text to the first truly successful intercontinental ballistic missile