Considering Apple has more CASH than the US Government does, I'm not sure I see that as a stumbling block. As I said above, they'd just be another content provider at that point.
As sad as it is to say, that's not saying much.
Satellite television networks alone (broadcast network retrans fees and advertising not included) collected $25B from the cable and satellite providers and $22.3B in advertising revenue during 2010. And on average those numbers increase 9% annually. That's $47.3B in 2010, $51.5B in 2011 and $56B in 2012, etc., etc. ad infinitum or at least until the drones get tired of Honey Boo Boo, NCIS: Panacea, Dancing with the Tards, etc.
Speaking in oversimplified, gross generalizations, that means Apple would have to negotiate with every network and write a seriously big check each year to replace or offset the lost programming AND advertising revenue that each network would lose by nullifying their existing programming contracts with cable and satellite providers... considering the current AppleTV has had limited success, Apple would be doing this on the come and chasing revenues that they may or may not actually be able to generate (in a timely fashion or otherwise). And of course you have to take into account bidding wars for premium content, such as DirecTV's NFL Sunday Ticket (which costs them $1B / year now and it only gets them exclusivity for games not already carried by local affiliates).
As soon as those contracts are nullified (there is a certain level of exclusivity granted to cable and satellite providers in return for confiscatory programming fees, mandatory annual rate increases and compulsory carriage requirements), the cable and satellite providers would start moving high-cost and/or low-viewership channels from the (currently mandatory) basic line-up and into programming tiers (all technically feasible now that cable and satellite have (for the most part) dumped analog video distribution)... which has a detrimental effect on both programming fees (maybe higher per sub, but far lower volume - i.e. I'm dumping Disney, MTV, etc. first chance I get) and advertising revenue (less exposure for new programming to channel surfers and fewer potential eyeballs for advertisers). And of course this doesn't take into account programming agreements outside of the United States.
The numbers might work if Apple could get 10M $1,500 televisions into 10M households and have each household immediately start spending their current television bill ($50-100 per month) in programming every single month... but that doesn't happen until you have the content and based on the AppleTV's performance so far, it would be a HUGE risk (I use my Gen2 AppleTV to watch documentaries on Netflix and an Itunes movie once every few months, so I'm a long way from even $50/month).
Now you could also say that Apple should go out and start buying media companies. Unfortunately a $150B war chest doesn't get you much more than Disney ($88B) and maybe Viacom ($27.5B) and/or CBS ($23B) at their current market caps... and that's not taking into account the inevitable stock run-up that occurs when acquiring a public company... then of course there are the lessons learned (or not) from the AOL Time-Warner merger (among other lackluster major media mergers over the years)... and the anti-trust issues... and you still only have access to a portion of the available media and you're now competing directly with the other media companies who you need to be negotiating with to get their content on to your platform.
I'm not saying that cracking the content nut is impossible, I'm just saying it is a mess and (unlike the music industry a decade ago), the networks have very little incentive to change things much as long as they can continue to have their cake and eat it too (predictable and reliable revenue growth from both programming fees and advertising revenue).
And apparently Apple is not willing to integrate a CableCard Slot into their rumored television product (ala Tivo), for any number of reasons, even though it would give them instant access to every household in the US that can be served by a cable television operator.
It seems even less likely that Apple could stomach a deal with Comcast, Time-Warner, FIOS, etc. to integrate their respective next-gen IP / Cloud video platforms into an "Apple Television" product. Of course Apple was able to stomach a deal with AT&T to get into the cell phone market, so maybe they can do the same with some or all of the incumbent video providers (even though such a deal would be perceived as a huge sell-out by those most desirous of an "Apple Television" that want it to be a way to "stick it to the man", i.e. their cable or satellite provider).
