The world has a long memory; true propaganda, distorting or outright lying about the actual facts, is going to be quite apparent later.  It's fine for Russia to be proud of themselves, but it seems like they have been embarrassing themselves frequently.  In the unlikely event that we elect Trump, we might return the favor for a while.  But everyone would see through it and know it would stop in 4 years, so it would likely be more humorous than anything.  The US is too open and too self-examining in public for much false propaganda to get very far for long.

I'm not sure that American Sniper is propaganda, even unintentionally.  Seems mostly like highlighting the sad situations people have allowed to happen.  Perhaps in the Strongest Tribe sense it has some weight, but snipers are a narrow, special breed.  I would think that the magical hand of God like drone war would have more weight.  The effect depends on what those people are thinking: Do they realize that they can never win in any serious sense?  Do they care or are they fine with just proving a point?

The US almost completely holds back on propaganda / education in the world, maybe for fear of or a general policy against being seen to be promulgating propaganda.  In most cases, where media and news and the Internet flow openly, it isn't really needed.  However, when hardly anyone in Afghanistan knows anything at all about 9/11 or similar, that is a failure of the world to provide even basic knowledge to everyone.  Separate from that, just understanding how a modern culture works, whether the US or Europe or any other high-functioning society, would be an important thing for some seriously problematic masses of people to know.  I don't care who causes effective education to bring these people up to date with understanding modern cultures, but it needs to happen.  In the absence of some other paths, it would seem like an important strategy for both US State and Defense, but I don't see it happening much.

The US has no need to try to make people like it; that should not generally be a goal.  But the world, especially including the capable Western world, both governments and populations, has a responsibility to educate those with abject ignorance, poverty, and knowing nothing but conflict that there are better ways of being, limitless opportunities, and that they could effectively work to modernize and become effective societies and cultures.  We need something similar to 'genocide' to identify pathological ignorance, recognize that it leads to the ruin of many lives, and determine how to take action to stop it.  There is no need for each culture to be exactly like the West or a particular form of government, but they should understand the options, understand how things can work effectively and why, and be able to incorporate elements in a local way to eventually make it work.  We need to decide how hands off we should be in allowing large areas to fumble about without making progress and even regress.  The prime directive should only apply to societies that are functioning to a reasonable degree.

An interesting question is whether and how poisoned thinking, i.e. bad memes, are shared, instilled, and propagated to eventually create terrorists and criminals:  What should we do to prevent spreading poisonous ideas?  Should we be rooting out bad imams, literature, religious leaders?  Ideally, our values and culture is an effective answer to these sources, but, just like in the biological world, eventually a successful defense will occur.  If you've read The Selfish Gene, you know that truth, rightness, or goodness are not the goals of particular genes or memes (ideas).  The only thing that determines success is successful competition and replication.  Our Western ideas can successfully compete and replicate against these bad meme sets, but only if they are present.  We seem to be in a situation where some of our allies are supporting the teaching of memes that are directly opposed to modern knowledge, including social and political knowledge.  What should we do about that?

All of this is crosscutting to security, encryption, communication, publishing, and surveillance.  Distrust is healthy, and sometimes prudent.  And, if we fail totally as a modern society, we may need it to maintain a modern underground in our new dark ages.  In addition to safe commerce and social connection, and balancing government and keeping it healthy, we should even better organize and extend the ways that we help enlighten the ignorant while combating meme cancer.

I imagine that soon we'll have universally available Internet (LEOs for instance), ultra-inexpensive devices (smart phones are down to $50 or less now), and organized, complete, and effective educational material that is somehow available, safe, and effective for everyone.  There should be some kind of support systems of various kinds, to the extent possible.  We are failing for not working toward these kind of things effectively enough.