f0f70a3c_ARPANET_motivations
It is inaccurate to say that the chief motivation in creating the ARPANET was to create a network that could withstand nuclear conflict, where mulitple nodes could be hit and the network could still go on functioning.
Ideas that originated from this concern did influence the project (chiefly 385af4b4_baran_distributed_networks at RAND), but this was not the concern of the ARPANET.
ARPA’s objectives were focused more on reducing efficiency in the academic and military projects it sponsored.
Different models of computer were used throughout the military-industrial-academic complex. Users required different logins and a knowledge of different operating systems and programming languages in order to be able to use them.
At the same time, there was a duplication of hardware. Different projects would all require their own computer to do their research. It would be better if the same computer could be accessed by multiple teams through time-sharing (already in existene) and a network.
Finally, results from different research projects were being duplicated. Different teams would be producing the same data independently of one another because the data could not be readily shared. If this redundancy could be removed, and the data accessed and shared between multiple projects, teams could focus on new research and the production of novel applications.