Introduction: This is a tweet from David Silverman (President of American Atheists) defending the practice of placing billboards critical of religious views in public places.
Key Facts: David Silverman is the President of American Atheists which is a non-profit organization promoting the interests of nonbelievers in the United States. Under Silverman’s leadership, American Atheists have put up a number of public billboards promoting atheism and criticizing religion. These billboards have themselves drawn criticism from religious figures and in some non-believers as well. Some of the criticisms have been directed at specific themes and specific statements included in the billboards. Others have been directed against the general wisdom of putting such statements out into the public.
Text: This is the tweet in question.
Comments: Two general points come to mind when considering this argument.
One is the possibility of a double standard in reference to billboards expressing a stance on religious topics. Christians in particular have been accustomed to producing such statements for as long as some of us can recall. The placement of anti-religious sentiments on a public billboard is however a relatively new practice, and it may draw more criticism due in part to the unusual nature of the messages. Simple confirmation Bias may be another factor insofar as the bulk of the public is unlikely to agree with an overtly atheistic message.
A second concern lies in the potential obfuscation of specific concerns about specific billboards. While this particular tweet addresses the issue in the abstract, some of the concerns raised about these billboards have been about very specific details about specific billboards put out by American Atheists, This is particularly true of those raised by unbelievers – whom Silverman presents as the party he intends to answer here.
Statements: The argument is set out as follows. Two missing statements  and  have been added.  helps to seal the relevance of statements 2 and 3 to the rest of the argument and  is most likely the intended conclusion of the argument.
 Atheists who object to billboards attacking religion are ALSO victims of religious indoctrination.
 Lies deserve death.
 [Lies do not deserve] Protection.
[] [Religious claims are lies.]
[] [Atheists ought not to oppose billboards attacking religion.]
Discussion: Issues raised by this argument include the following; ad hominem, Interactional eclipse, micro-reasoning, missing statements, the principle of charity, provincialism, and thought policing.
Ad Hominem: The assertion that critics (atheist or otherwise) of billboards promoting atheism are victims of religious indoctrination is an ad hominem (circumstantial). If there is a non-fallacious way to interpret that suggestion it would be to treat it as a simple explanation to be taken at face value. In others words, it would be possible to simply think of this as an empirical question about the motivations of a select group of people. The second statement in the tweet, however, belies this interpretation as it makes it clear Silverman means to argue with his critics. This is not simply a diagnosis; it is an attempt to undermine the credibility of billboard critics.
Interactional Eclipse: To the degree that this argument constitutes a form of thought policing, it is explicitly an attempt to subvert efforts to engage in critical thinking about the value of anti-religious billboards through appeal to social dynamics. Whatever the value of the argument, any resulting debate is more likely to generate more heat than light.
Micro-Reasoning: As with most (if not all) tweets, the brevity of this argument is a problem, hence the need to supply nearly as many missing statements as those clearly expressed.
Missing Assertions: The intended conclusion of this argument is most likely some statement intended to discourage unbelievers from engaging in criticism of billboards promoting atheism. I have accordingly supplied statement 5 as an attempt to express this missing statement.
I would also suggest an additional Missing Assumption (statement  that religious views are lies). If this assumption is not true, then both statement 2 and 3 fail to produce anything of value in the argument.
Principle of Charity: It isn’t entirely clear whether Silverman means to suggest this argument applies to all instances in which atheists prove critical of billboards attacking religion or simply those who do so on principle (I.e. those who object categorically to the creation of such billboards instead of those with particular objections to specific billboards). His wording could facilitate either interpretation, and it is likely those who agree with him will include parties adopting each interpretation.
For purposes of keeping the discussion thoughtful it is probably best to treat this argument as applying only to those who object to such billboards in general. The alternative would in effect amount to a blank check to produce any content (no matter how foolish) critical of religion without fear of counter-criticism from other atheists. That would hardly be a reasonable position, so it’s not the most productive interpretation of the argument to pursue here.
Provincialism: Insofar as this argument seems to be encouraging atheists to be less like religious people, it could be viewed as an appeal to provincialism. Essentially, the appeal here is something along the lines of; ‘this is how WE act” or even “this is how WE should behave.” Well, WE (i.e. atheists) may or may not typically fall prey to religious indoctrination, but that appeal isn’t very cogent.
Thought Policing: One of the more compelling features of this argument lies in its implied comparison with believers. It is not merely that Silverman is suggesting that his atheist critics have been indoctrinated; he is reminding atheists that the conduct in question is unbecoming for unbelievers..This is classic thought policing., which goes a little beyond the normal ad hominem to invoke peer pressures and trigger loyalties associated with group membership. Just how significant such loyalties may be for atheists is an interesting question, but the argument still works this angle. The social dynamics at issue thus overshadow the rational significance of the argument itself.
Diagram: I take it that 2 and 3 are intended (with missing assumption  to prove statement 1, which is in turn intended to demonstrate the truth of the missing conclusion (statement 5).
2+3+ -> 1 -> .
Evaluation: Let’s consider both inferences:
2+3+=>1. The truth of each of the assumptions in this inference would certainly be debatable. It isn’t clear that religious claims are all untrue (much less that they are lies), nor is it clear that lies deserve death (which is presumably a metaphor indicating the discrediting of such claims and a hope that they will eventually cease to circulate). If we assume by protection that Silverman means only protection from criticism (and not protection from coercive sanctions, then perhaps statement 3 fairs reasonably well in the truth evaluation, though a creative thinker could probably find a reason to protect at least some lies.
The inference itself fairs no better. It isn’t clear that objections to the billboards are offered in an attempt to ‘protect’ religion. Nor is it clear that the billboards play any constructive role in advancing the demise of religious beliefs.
If one doesn’t assume the charitable interpretation of Silverman’s intent, the problem becomes still sharper insofar as specific concerns about specific billboards may well address the effectiveness of those billboards in advancing a critique of religion.
4 -> 5: This is arguably an ad hominem (circumstantial) and/or an argument from Provincialism, as outlined above. In either event, the inference would be fallacious. Also, the argument side-steps the possibility that atheists might have reasons to oppose the billboard campaign other than latent sympathy for religious sentiment.
Also, if we do not adopt the charitable interpretation of Silverman’s position, it seems clear that atheists (even those who genuinely hope to confront religion whenever possible) may have a number of concerns about specific messages contained on specifi billboards.
I think the argument has to be considered unsound.
Final Thoughts: In the end, this argument does strike me as a simple effort to engage in thought policing. It effectively urges atheists to support their own camp regardless of any concerns they may have about the specific messages placed on these billboards or the general effectiveness of public billboards as a means of challenging religious views.