Not necessarily; I don't think they're quite stupid enough to think that encryption is not needed. (Perhaps once upon a time that was the case, when encryption was a munition regulated by ITAR.)
Rather, politicians are under the impression that it is, or should be, possible to have encryption that protects against anyone except their own government, that that's something they should get to ask for in the first place, and that that's just as good as un-broken encryption. None of those things are true, but good luck telling a politician that something necessarily needs to be beyond their control in order to function correctly.
This -- until people realise that their online banking is not secure without encryption. That puts it firmly into the second category for many people.
(It's my experience that people are more worried about their money than their dick pics.)
For some time, only online banking was allowed to use strong encryption on the web. There was a special kind of certificate, which could be issued only to financial organizations, which told browsers they were allowed to use strong cipher suites.
For one thing, most people have at least some money, while the desire to photograph one's genitals (and especially, after having done so, to keep the results private) is relatively rare.
I never understood that position. Based on the argument that encryption is a mechanism for speech, why not classify it as speech?
Politicians think encryption is in the first category.
Edit: given how this discussion is going, I think we're back to the idea that encryption should be classified as a weapon in the US and subject to second amendment protection, as the 2nd is much more strongly defended than the 4th or 5th or even the 1st. (This argument obviously doesn't make any sense in the UK, where we should lean on article 1 and 6 ECHR). A country where you can have an AR-15 but not AES-CBC makes no sense, but we have to work with the politics as they are.
http://www.pcworld.com/article/2044529/decryption-orders-cou...