While the strategy of pushing the Việt Minh into attacking a well-defended base in a remote part of the country at the end of their logistical trail was validated at the Battle of Nà Sản, the lack of construction materials (especially concrete), tanks (because of lack of road access and difficulty in the jungle terrain), and air cover precluded an effective defense, culminating in a decisive French defeat at the Battle of Dien Bien Phu.