Original text:
Abstract This document describes the technical mechanisms used by censorship <del> regimes around the world to block or degrade Internet traffic.  It </del>  aims to make designers, implementers, and users of Internet protocols aware of the properties being exploited and mechanisms used to censor end-user access to information.  This document makes no suggestions 1.  This document describes the technical mechanisms used by censorship <del> regimes around the world to block or degrade Internet traffic (see </del>  RFC7754 for a discussion of Internet blocking and filtering in terms of Internet architecture).  To that end, we describe three elements <del> of Internet censorship: aggregation, identification, and prevention. Aggregation is the process by which censors determine what they should block, i.e. they decide to block a list of pornographic websites.  Identification is the process by which censors determine whether content is blocked, i.e. the censor blocks all webpages containing "sex" in the title.  Prevention is the process by which the censor intercedes in communication and prevents access to censored materials. </del>  2. <del> Aggregation is the process of figuring out what censors would like to block Glanville-2008.  Generally, censors aggregate "to block" </del>  information in blacklists or using real-time heuristic assessment of content Ding-1999.  There are typically three types of blacklists: Keyword, Domain Name, or IP.  Keyword and Domain Name blocking take At all levels of the network hierarchy, the filtration mechanisms used to detect undesirable traffic are essentially the same: a censor sniffs transmitting packets and identifies undesirable content, and <del> then uses a blocking or shaping mechanism to prevent or degrade </del>  access.  Identification of undesirable traffic can occur at the application, transport, or network layer of the IP stack.  Censors are almost always concerned with web traffic, so the relevant 3.3.2. Censors sometimes identify entire protocols to be blocked using a <del> variety of traffic characteristics.  For example, Iran degrades the </del>  performance of HTTPS traffic, a protocol that prevents further analysis, to encourage users to switch to HTTP, a protocol that they can analyze Aryan-2012.  A simple protocol identification would be to somewhat challenging from a QoS perspective. Empirical Examples: Packet Dropping is a very common form of <del> technical prevention and lends itself to accurate detection given the unique nature of the time-out requests it leaves in its wake.  The Great Firewall of China uses packet dropping as one of its primary mechanisms of technical censorship Ensafi-2013.  Iran also uses Packet Dropping as the mechanisms for throttling SSH Aryan-2012. </del>  These are but two examples of a ubiquitous censorship practice. 4.2. Trade-offs: RST Packet Injection has a few advantages that make it extremely popular as a censorship technique.  RST Packet Injection is <del> an out-of-band prevention mechanism, allowing the avoidance of the </del>  the QoS bottleneck one can encounter with inline techniques such as Packet Dropping.  This out-of-band property allows a censor to inspect a copy of the information, usually mirrored by an optical BitTorrent Schoen-2007, this later led to a US Federal Communications Commission ruling against Comcast VonLohmann-2008.  China has also been known to use RST Packet Injection for censorship purposes.  This <del> prevention is especially evident in the interruption of encrypted/ </del>  obfuscated protocols, such as those used by Tor Winter-2012. 4.3.

Reviewer comments:
…nce. defines censorship. fixes definition of identification in intro.
First, one thing that isn’t clear immediately from the introduction is who/what is a “censor”. I find it a little strange, actually, to suggest that a censor performs "aggregation". Is the censor an ISP? A government? Something else? For example, a government may have loose policies about what kind of content to censor (e.g., "hate speech"). An ISP might in turn implement these loose policies in different ways. Policies can also differ across a country, etc. The other terms---identification and prevention---are similarly confusing, although I think the term "identification" isn't as problematic as its (incorrect?) definition in the introduction. "Identification is the process by which censors determine whether content is blocked" - NO. I think it is the process by which a censor might classify traffic to determine whether to block a traffic flow or now. I would suggest something like: prescription, identification, and interference.
Wondering what you think about "design, identification, and interference"? I think for the purposes of todays 20:00 ET IETF drafts deadline, I'll change the terminology throughout to match prescription, identification, and interference and I'll correct the other things mentioned here (define censor, fix definition of identification in intro).
That seems a bit more clear, indeed! Ah, I didn't realize there was a deadline of today 2000h. Not sure I can get you a pull request by then, but will try.
I'll leave this open. You by no means need to get a pull request by 20:00! I just want to do my best to make changes responsive to your feedback. I'll leave this open and you can see what I've done (I'll be working on trying to clear out issues until then), and feel free to submit changes as you think are needed.

Revised text:
Abstract This document describes the technical mechanisms used by censorship  <ins> regimes around the world to block or impair Internet traffic.  It </ins> aims to make designers, implementers, and users of Internet protocols aware of the properties being exploited and mechanisms used to censor end-user access to information.  This document makes no suggestions 1. <ins> Censorship is where an entity in a position of power - such as a government, organization, or individual - supresses communication that it considers objectionable, harmful, sensitive, politically incorrect or inconvenient.  (While censors that engage in censorship or establish censorship regimes must do so through legal, military, or other sources of power, this document focuses largely on technical mechanisms used to achieve network censorship.) </ins> This document describes the technical mechanisms used by censorship  <ins> regimes around the world to block or impair Internet traffic (see </ins> RFC7754 for a discussion of Internet blocking and filtering in terms of Internet architecture).  To that end, we describe three elements  <ins> of Internet censorship: prescription, identification, and interference.  Prescription is the process by which censors determine what types of material they should block, i.e. they decide to block a list of pornographic websites.  Identification is the process by which censors classify specific traffic to be blocked or impaird, i.e. the censor blocks or impairs all webpages containing "sex" in the title or traffic to sex.com.  Interference is the process by which the censor intercedes in communication and prevents access to censored materials by blocking access or impairing the connection. </ins> 2.  <ins> Prescription is the process of figuring out what censors would like to block Glanville-2008.  Generally, censors aggregate "to block" </ins> information in blacklists or using real-time heuristic assessment of content Ding-1999.  There are typically three types of blacklists: Keyword, Domain Name, or IP.  Keyword and Domain Name blocking take At all levels of the network hierarchy, the filtration mechanisms used to detect undesirable traffic are essentially the same: a censor sniffs transmitting packets and identifies undesirable content, and  <ins> then uses a blocking or shaping mechanism to prevent or impair </ins> access.  Identification of undesirable traffic can occur at the application, transport, or network layer of the IP stack.  Censors are almost always concerned with web traffic, so the relevant 3.3.2. Censors sometimes identify entire protocols to be blocked using a  <ins> variety of traffic characteristics.  For example, Iran impairs the </ins> performance of HTTPS traffic, a protocol that prevents further analysis, to encourage users to switch to HTTP, a protocol that they can analyze Aryan-2012.  A simple protocol identification would be to somewhat challenging from a QoS perspective. Empirical Examples: Packet Dropping is a very common form of  <ins> technical interference and lends itself to accurate detection given the unique nature of the time-out requests it leaves in its wake. The Great Firewall of China uses packet dropping as one of its primary mechanisms of technical censorship Ensafi-2013.  Iran also uses Packet Dropping as the mechanisms for throttling SSH Aryan-2012. </ins> These are but two examples of a ubiquitous censorship practice. 4.2. Trade-offs: RST Packet Injection has a few advantages that make it extremely popular as a censorship technique.  RST Packet Injection is  <ins> an out-of-band interference mechanism, allowing the avoidance of the </ins> the QoS bottleneck one can encounter with inline techniques such as Packet Dropping.  This out-of-band property allows a censor to inspect a copy of the information, usually mirrored by an optical BitTorrent Schoen-2007, this later led to a US Federal Communications Commission ruling against Comcast VonLohmann-2008.  China has also been known to use RST Packet Injection for censorship purposes.  This  <ins> interference is especially evident in the interruption of encrypted/ </ins> obfuscated protocols, such as those used by Tor Winter-2012. 4.3.