City of Roses
Yeah, though I'm certainly no fan of Rush Limbaugh, all in all I agree with your theories on why Limbaugh has achieved the level of popularity he has, and why he has widely influenced public discourse within the last three decades.
I would add as a fourth reason that he strikes the curiosity of people from both sides of the aisle (same with O'Reilly). I actually believe quite a bit of his weekly net audience are Democrats and those who actually staunchly disagree with him, who tune in out of curiosity to hear what inflammatory piece of rhetoric he'll conjure up next, and eyeing him like a hawk in understanding his usual on-air personality demeanor and format so the Democrats can adopt his approach as a left-wing equivalent of it, which in fact I think Ed Schultz has attempted to do, deeming himself the "Rush Limbaugh of the Left".
Just a note regarding your third point, however. Limbaugh, too, has resorted to frequent negative attitudes as well whenever Democrats were in power. In fact, immediately when Bill Clinton was elected president in 1992, Limbaugh started the "America Held Hostage" segment, which is telling in that, though I certainly sympathize with everyone sick of all the Democratic Party's corruption in Congress at the time, he never even wanted to give Clinton a chance to begin with and had a biased grudge against him from the start, simply because he shared the name of the party that was tainting Congress.
So essentially Limbaugh has been exactly during the 90's what Air America is right now; spending all one's breath seeking retribution on political opposition without declaring a vision for a positive alternative; calling to impeach Clinton, making up all kinds of conspiracy theories about the Clinton family (such as Hillary being involved in the 1993 suicide of deputy White House counsel Vincent Foster) like some Air America personalities do about the GOP being behind Pall Wellstone's death, and so-forth. Moreover, he too demonizes those he doesn't ideologically agree with, including saying, "What's good for Al Qaeda is good for the Democratic Party.", once calling abortion rights activists "feminazis", and even saying outrageous things like referring to prisoner abuse at Abu Ghraib as "blowing some steam off".
Despite my strong opinion that Limbaugh resorts to his own brand of negativity just as much as the Jeanane Garofalos of Air America, I do think his entertaining persona and his tempering of curiosity explains his wide influence on the airwaves today, even when I think his program is about as biased as it can get.
I think it's just that same sort of appeal that explains the rising popularity of Keith Olbermann on MSNBC, who hosts "Countdown". Being a former ESPN sportscaster and anchor personality, and a great fan of sports in general, Olbermann has a very unique anchor personality, which I like to think of as the Jacques Servin or Igor Vamos of cable news, welded into the dress suit of a contemporary Edward Murrow and straightened up with the mandarin collar of a Broadway aficionado.
I think Olbermann has slowly but consistently continued to strike the curiosity of the general public in that he too touches up on harder-news stories most other media outlets won't ever cover (like going into deep detail of the recently-signed Military Commissions Act and its implications to the definition of torture and executive power, and the growing KBR-Halliburton scandals) while also balancing the serious news with a lighter news segment known as "Oddball" and airing positive stories as well including the Amish community and their forgiveness in ligh of the recent tragedy. Also, I think there's an appeal in that he treats his guests with respect, in that he never interrupts them in the middle of any question (including John Ashcroft two weeks ago) and lets them say what they want to say, unlike what personalities like O'Reilly do in interrupting individuals he doesn't agree with.
Olbermann, too, can certainly be inflammatory at times, particularly in his "Special Comments" where when something the current Administration especially troubles him in the news, like with the signing of the Military Commissions Act without habeas corpus guarantees or the sluggish response to Hurricane Katrina, he dedicates 7-10 minutes in an essay sort of format in a no-prisoners sort of anchor approach, criticizing its leadership while also documenting other historical accounts of similar negligence.
Those "Special Comments" are tough indeed, and I don't agree with his tone at times, but in the general sense the main points he makes in them are quite convincing and appear thoughtfully researched, and I think they explain how his ratings have really soared in recent months, standing out among an otherwise poorly-rated network; much of the American public believes the Bush Administration is not being fully honest with the American people on Iraq and other issues, the're not hearing what they want to hear from them, and so they curiously hear Olbermann out, regardless of how much they agree or disagree with him, because he provides some interested grains of truth that get expressed minimally in the rest of the cable news environment.
"If we have no peace, it is because we have forgotten that we belong to each other"