I am not skilled enough to provide you a technical analysis. It's only questions... Could the UN bans certain ip range or ban ports? Simply put can they have an influence or effect on Bitcoin networking? I am speaking on a trustless basis.
Technically, they could cause issues to the participants of the BTC network in a dark future by banning certain IP ranges or ports or using other means, but thanks to the BTC network's decentralized nature I doubt they could cause issues to the network itself. Furthermore, before they could do it, they would need to challenge several legal issues and resolve them until they get to the point when they can execute such a plan. So, no, they cannot and even if I was wrong, you would know about it in time and you would still have time to prepare and re-configure your equipment.