`  == Not a deterrent ==  In the previous version of this article, the R-16 was referred to as ``the first truly credible rocket-based nuclear deterrent`` in the Soviet arsenal.  This is inaccurate  the long response time and unprotected launch facilities meant that the R-16 was a first-strike 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.  I've changed the text to ``the first truly successful intercontinental ballistic missile``.   `