The Polaris going on line, as well as reliable ICBM’s, is why Kennedy was looking to phase out the PGM-19 Jupiter before the Cuban Missile Crisis. The Jupiter was also a stopgap, as well as obsolete shortly after it was deployed.
I always thought it was neat how the first US nuclear cruiser (the Long Beach) was supposed to have first a Regulus launcher then a vls farm amidships for eight Polarises. Ended up putting the ASROC box there instead. And the 5” guns Kennedy himself ordered in after a tour.
RP-1 and LOX didn’t make for very reliable rockets. I was 7 - 9 years old when all the crashes were occurring regularly at Canaveral. Dad subscribed to Aviation Week and I recall the steady stream of articles about failure after failure. Then all the Redstone and Atlas failures about the same time. It was an exciting time to grow up (if you weren’t too worried about getting incinerated by a Rusky nuke — but scrambling under your school desk was going to save you).