If you're referencing the Gary Powers incident, it's worth noting that flying high altitude spy missions happened in the years before satellites were sophisticated enough to do what those planes were doing. How we would see a high altitude surveillance operation is drastically different after the advent of spy satellites than before.
As far as it being a weapon, it's practically useless in this day and age due to its lack of propulsion. Weapon balloons became obsolete during WWII with the deployment of radar batteries, and they're even less useful with the advent of those same spy satellites and GPS in addition to more advanced radar.