Another layer of a cryptic Dish Network plan for its future was peeled back today when the nation’s second-largest satellite TV provider formally asked the U.S. government permission to offer a mobile high-speed Internet service. The move brings into clearer focus Dish’s potential goal: building a mega video-streaming service for itself and its newly acquired Blockbuster on a network that would bypass the broadband pipes of its cable competitors. Dish and chairman Charlie Ergen have been on a buying binge of late, including acquiring spectrum from DBSD North America and TerreStar Networks; those are the assets that Dish is asking the government to clear, according to an FCC filing, which would allow the high-speed plan to move forward. During Dish’s 2Q earnings call this month, CEO Joe Clayton said the company would not “tip its hand” to plans, but that “video is our primary objective,” including having broadband-connected set-top boxes for its subscribers and adding licensing arrangements for Blockbuster that could include subscription VOD. Its own high-speed service would supply all of this and makes sense, but the question remains how much will such a network cost to build? Already, Credit Suisse Group AG analyst Jonathan Chaplin has weighed in on that one, saying it could be “costly.” As with everything Dish-related, stay tuned.