there is several projects aimed at running windows binaries, one of them being an NT clone, dos clones already exist and can be made to run windows dll's on top for an olde worlde windows, and of course wine. i personally hope what it will involve is a bsd core running a customised and advanced wine fork, i mean, considering brazil and several other countries are going linux and open source it would be stupid of them to not collaborate with their fellow rising industrial stars like brazil who iirc are moving their government IT over to open source. a 99.9% binary compatible framework to run windows apps would be beneficial for everyone who is not NATO, indeed i can imagine some of the more client-agnostic big tech contractors who help build military stuff would love to be able to sell their windows-targeted software to someone else... brazil, india and russia at least would all be interested, china is too closed to alliances in any way but who knows, if india gets their project off the ground and achieve their goal.
remember, a lot of those windows programs are now partially developed by indians... if anyone can make a fully binary compatible windows environment, it's india. they've been doing so much of american-based multinational corporations' development already they have a rich developer skills base.