Reagan went full bore with the arms race as soon as he came into office.
Remember the “Strategic Defense Initiative” which was referred to as “Star Wars”? It scared the hell out of the Russians. This was about the time that the IBM PC came out. We were crushing the Russians with huge technology leaps. It pushed the Russians over the edge economically.
I've been hearing that meme for decades. The Russians had an ABM system already. The were also investing in a blue water navy. That was the big demand for cash, particularly for upkeep. They paid for it with oil revenues, their only source of foreign exchange at the time. When the price of oil dropped, that revenue dried up.