FOX probably has what it takes (out of the rest of the OTA networks, ignoring Telemundo/NBC) to launch a Spanish network. It's already got soccer contracts for its cable outlets, for one, and MyNetworkTV scored well initially in Hispanic markets with its telenovelas. But I hope they managed to learn some lessons from the MyNetworkTV failure, both about competing with yourself and about ambition/Murphy's Law. I remember that MyNetworkTV was intended to be profitable from day one (and it was on course to, until the actors unionized).
Of course, competing with yourself may not be as big of an issue here as it was with MNTV. If two markets are mutually exclusive (like men's razors vs women's razors), you don't really need to worry too much about self-cannibalization. So, how separate are the two markets? A majority of English speakers in the US probably do not know Spanish well enough to follow Spanish TV, but I suspect that a larger percentage (maybe even a majority) of the Spanish speakers in the US know enough English to follow English TV. But I don't know enough about the TV watching habits of people (of either language) who watch Spanish TV to be able to conclusively state that.
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