Preface: I don't think this is a likely explanation. But if you think it is, there's a big advantage of kinetic weapons over ICBMs, namely that they are a lot

Preface: I don't think this is a likely explanation. But if you think it is, there's a big advantage of kinetic weapons over ICBMs, namely that they are a lot more credible as a first strike weapon. ICBMs launches are quite detectable, allowing counter strikes (hi there nuclear deterrence).