Mog,
I know there is some transfer of technology. I spent 6 years working with industry and 3 with MoD PE. However, these days the transfer is more civil to military (COTS is the most used term in any military aircraft spec these days)
I'm not saying don't develop it or buy it but just that one has to justify it on better grounds than 'if we don't buy then we won't have an industry left'
Also, the increased cost of operating a diverse fleet must be taken into account. like it or not, if you have a civil derivative then spares are easily found anywhere in the world. Have a specific military type and you are on your own!!