The development of T-Mat ultimately led to the abandonment of manned space programmes, with the only launch vehicles remaining being those required to place satellites in terrestrial orbit. It apparently never occurred to anyone in charge that the transmat link between Earth and the moon might one day catastrophically fail beyond the capacity of the moonbase personnel to repair. The Ice Warriors exploited this weakness when they took over the base as a beach-head for their ill-fated invasion of Earth; a corollary of this compromise of the network was a disastrous collapse of global food distribution. (TV: The Seeds of Death)