This may seem surprising in the light of Botvinnik's results in the 1950s and early 1960s, when he failed to win a world championship match outright (as reigning champion) and his tournament results were patchy. But after the FIDE world championship cycle was established in 1948, reigning champions had to play the strongest contender every three years, and successful title defenses became less common than in the pre-World War II years, when the titleholder could select his challenger. Despite this, Botvinnik held the world title for a longer period than any of his successors except Garry Kasparov. Botvinnik also became world champion at the relatively late age of 37, because World War II brought international competition to a virtual halt for six years; and he was 52 years old when he finally lost his title (only Wilhelm Steinitz and Emanuel Lasker were older when they were defeated). Botvinnik's best years were from 1935 to 1946; during that period he dominated Soviet chess; and the USSR's 15½–4½ win in the 1945 radio match against the USA proved that the USSR's top players were considerably better than the USA's (who had dominated international team competitions in the 1930s).