Hey gang. Next wednesday I'm gonna go over our left party's stance on NATO (against) and explain why our me and our party thinks NATO is bad. I know they've done nasty shit in Yugoslavia, Libya, Iraq, etc. I'm gonna go at it from a purely anti-war perspective, as I won't assume everyone listening to my talk is necessarily convinced of socialism. What I could really use at this point are credible sources pointing to NATO and the USA starting offensive wars to profit off of doing horrible shit. Anything from the founding of NATO to today is good. Any help is appreciated, thank you.
This is going to be a pretty basic introductory talk, but if you have more high-level things you want to talk about, feel free to post them as well just for fun. 
Who was threatening Poland or Hungary in 1999? Russia was a capitalist liberal state that was barely holding itself together, much less menacing central Europe.
EDIT: To expand on this, there would be no crisis in Ukraine if the US/NATO had treated Russia with half the magnanimity that they treated Nazi Germany. They had won the Cold War, and the new Russian ruling class wanted to be capitalist liberals like their counterparts in the west. It was the combination of an idealist/moralist urge to twist the knife and a insistence on singular US hegemony over Europe that kept Russia out of the club of "1st world nations" and led to Russia's continued alignment with the west's remaining enemies.
Yes. And in addition to that, the existence of NATO wouldn't even be a thought and we wouldn't need to currently be hoping to disband it if Russia wouldn't be a risk (currently a risk which materialized)
Again, who is modern Russia a risk to? Yeltsin and Putin were/are both capitalists, both happy to supply raw resources and energy to Europe, and both acceded to the independence of the former SSRs. It was only after the US's open funding of anti-government rebels in one of Russia's key remaining allies (Syria) and the 2014 coup in Ukraine (related to Russia's valid concerns over the Ukraine-EU trade deal that would have violated their standing free trade agreement with Ukraine and allowed asymmetrical tariffs between EU and Russian goods) that pushed Russia into open antagonism with the west. Up until this point, Russia was behaving like every other eastern European country, there was no legitimate threat from Russia.
When it comes to Ukraine, Russia has a real material interest in keeping the country as at least neutral. It was a massive trading partner, has a massive land border, access to nuclear power, there's a large Russian-speaking and ethnic Russian population stranded by the dissolution of the USSR, and can't forget the importance of Sevastopol as a port. Estonia, Lithuania, Latvia, and now Finland -> not actually a significant threat or red line when it comes to joining a hostile bloc, but Ukraine was a line too far. What would the US have done in Russia's place if Russia or China had done the same thing in Mexico? What if they had tried to strong-arm Mexico into a trade deal that would have allowed 3rd-party goods to enter US markets as NAFTA products? What if they had facilitated the Mexican president being forced out of power, which then allowed ultranationalist paramilitaries to start terrorizing border communities? Right now, we have US politicians that are advocating to invade Mexico for shits and giggles: I don't think you'd need to give them too much of a real reason.
What I'm saying, is that NATO is not a defensive alliance, but an aggressive one dedicated to anti-communism in general and eroding the USSR and now Russia more specifically. If NATO leadership was interested in peace and common defense in Europe, then they would be dissolving NATO in favor of a security architecture that includes all stakeholders in the region, as opposed to subordinating each country's military to the United States. This would have been incredibly easy to do, the Russian leadership have indicated their willingness for such an arrangement for a very long time, going back to even Stalin's proposal for the USSR to join NATO. Rather, it was NATO antagonism that kept pushing and pushing the line until they hit the button that permanently alienated Russia and dragged the world into a new Cold War.
Exactly. And Russia annihilated the chance of Europe building its own separate defence