Propaganda only works if ideas have power. If ideas have power, they can also change policy. So propaganda can change policy. The mechanism is people taking it seriously and putting pressure on their governments. That's my basic argument.
You have to distinguish who the propaganda targets and what those who legitimise their policies with propaganda have in mind or are impacted by. Efficient propaganda means the targets believe it, not necessarily those who conceived the propaganda. Hence a majority of the public opinion within the US can be sensible to ideas of "human rights", "freedom" and "liberty", but the political leaders, advisers and lawmakers who determine foreign policy might rather sensible to ideas of "free market", "business" and "anti-communism". The most successful propaganda in this scenario will be the one which successfully assimilates "human rights", "freedom" and "liberty" with "free market", "business" and "anti-communism". Does that mean that the ideas displayed in propaganda have power amongst those who make the decisions? Not necessarily, especially when imperialist "anti-communism" is anti-democratic, goes against human rights by breaching all basic liberties and limiting political freedom. The important thing for the propaganda is the ideas having power amongst the targeted audience.
I'm probably not going to convince you that the ideals stated in the Atlantic Charter were always part of the belief system of NATO leaders. That is what I think, but I also think they were pretty conflicted about it and frequently acted callously and hypocritically. So let's look at when those behaviors changed and what may have caused the change.
I never denied that behaviours changed, we disagreed on why the behaviour changed and the scale of change.
Pacifism was not a majority view even among the protesters, partly because they included some who wouldn't rule out violence to overthrow the current regime but also because many didn't disagree with defense against an invasion.
Let us not confuse foreign policy with domestic policy. You can be in favour of overthrowing the government violently but then once you are in power stop interventions abroad like Vietnam. On the other hand it is true that proponents of violent world revolution supported interventions abroad, but I would have to look at the numbers there.
defensive alliance is perfectly compatible with anti-imperialism, too.
NATO was not a defensive alliance in the eyes of the anti-imperialist protesters, it was seen as an agressive alliance serving US imperialism. That view was backed up by the fact that the US military dominated the alliance completely, which always aligned upon US foreign policy. Said military and intelligence frequently intervened aggressively abroad.
But then, as you say, many did indeed turn rightwards; and I would add: without too much struggle with their conscience, which shows IMO that the majority of the protesters weren't very ideological on these points.
Here I have more doubt, I don't see how individual shifts reflect that protesters weren't ideological or that the concerns were not founded in a coherent worldview. That rather reflects those protesters either becoming disillusioned and cynical, or simply becoming more wealthy and thus having an objective interest in now opposing such views. Others stayed true to their beliefs, and certainly were ideological.
My point, though, is that NATO could reduce that pressure by starting to live up to its stated ideals. The crucial event here is the 1974 Carnation Revolution in Portugal which overthrew a military government but didn't take the country out of NATO. Neither did the removal of the Greek colonels or the (repeatedly) restored democratic governments in Turkey. Some new governments were left-wing but center-left rather than radical, some were center-right. The end of the Franco regime also brought centrist governments that put the country on a pro-Europe and pro-NATO course. As NATO's dictatorial member states were democratizing (and one non-member joined after democratization), they brought NATO closer to its ideals. That reduced the pressure. To be clear, I am not arguing that NATO caused these transitions, these were national popular movements. I'm only arguing that they showed NATO that the paranoid view (overthrowing allied dictator = country goes over to the Soviet bloc) was wrong. None of this came from the top but the heads of government were quite happy with the result.
None of this is NATO living up to its ideal, in no case does NATO defend any population or encourage democracy in any way. It is merely NATO recognising a new de facto state of affairs, not NATO itself being the actor of a big shift. Things are happening, and NATO evolves as a consequence of events that are completely external to its own actions. The changes do indeed however show that the social movements have been weakened and the left marginalised, as the threat of the Soviet Union is reduced (meaning there is less of a need to counter-act in defence of the mixed economy with strengthening the welfare state) and economic crisis hits Western Europe after the Yom Kippur War leading to the 1973 oil crisis. This economic crisis, and the political, social and economic consequences of it, would be fatal to much of the labour movement, thus enabling a shift to the right of the whole society, including in foreign policy.
So this is where we differ. In my view, once popular movements from below showed the way, NATO governments (by and large, and in most but not all instances) did follow. In part this is because they saw the propaganda value and in part because domestic opposition following on from 1968 put pressure on those governments while members of that movement, who were serious about the ideals, gradually moved into government positions.
I disagree, there was a short period of pressure between roughly 1968-1973, but afterwards the counter-revolution was much more considerable and by 1980 you have for example Reagan and Thatcher triumphing with more reactionary values than the previous leaders.
It's true enough that the rainbow coalitions of 1989 and before quickly split into different parties which espoused ideals that the original rainbow coalitions hadn't espoused. That's quite common in revolutions, actually. The first stage in Russia 1917 and Iran 1978 was much less radical than the second stage.
Except that the 1989 transition opened up for several potential outcomes, both as radical. It could have lead to an a non-Marxist-Leninist form of socialism (worker cooperatives, self-government or other bold experiences), it could have meant strong welfare states similar to Scandinavia or it could be a very radical form of neoliberalism striving towards total market control and very little democratic control over the economy.
Going full capitalist would have been a dealbreaker in Solidarnosc, it wasn't a problem after the fall of the communist regime, in fact it did quite well in elections.
Solidarność's platform on which they won the elections in 1989 was fundamentally incompatible with market liberalism, defending worker cooperatives, so it is wrong to say "it wasn't a problem". A such considerable shift happened in completely anti-democratic circumstances, with IMF holding Poland as hostage, giving little choice but to destroy the public services and state ownership. Such aggressive liberalisation is the problem here.
Meanwhile those parties that propose a socio-economic order that resembles the old regime tend to lose support as its legitimacy crumbles (which for quite large numbers of people only happens after the regime falls, political psychology can be screwy).
I don't think anyone in this thread suggested the successors to the Communist parties had much of a chance in Poland. I agree with the argument but it doesn't really respond to what I said.
I wouldn't be surprised if foreign policy circles and secret agencies kept a close eye on the process but I haven't seen any evidence of anti-democratic means being used. Well, let me qualify that: there were certainly incidents of anti-democratic behavior on the parts of individuals and sometimes parties, a country doesn't go from dictatorship to perfect democracy in one single step. I've seen nothing on a scale that suggests to me that the process as a whole was anti-democratic. I would love to see your evidence, as well as @Andre Bolkonsky's (hopefully) upcoming essay.
I never said the whole process was anti-democratic, there you would have misunderstood me. There were free elections with pluralism, democratic liberties were put in place, with incidents as you say. That is not what I would cite as problematic, it is not the point of contention. The problematic aspect is that US-lead international institutions, such as the IMF, imposed a specific and very radical economic agenda, which was completely anti-democratic since it deprived voters of a choice and meant the elected government had no choice but to liberalise, deregulate and privatise. This is how the US ensured a country like Poland ended up like it wanted it to be.