Oh, they did? Let's look at how America prevented Africa from manufacturing HIV treatments

    """
    In 1997, South Africa tried one tack. It passed a law to allow the 
    importation of patented medicines that had been produced or sold in another 
    nation's market with the consent of the patent owner. For example, if the 
    drug was sold in India, it could be imported into Africa from India. This 
    is called "parallel importation," and it is generally permitted under 
    international trade law and is specifically permitted within the European 
    Union.
    
    However, the United States government opposed the bill. Indeed, more than 
    opposed. As the International Intellectual Property Association 
    characterized it, "The U.S. government pressured South Africa ... not to 
    permit compulsory licensing or parallel imports." 3 Through the Office of 
    the United States Trade Representative, the government asked South Africa 
    to change the law — and to add pressure to that request, in 1998, the 
    USTR listed South Africa for possible trade sanctions. 
    
    That same year, more than forty pharmaceutical companies began proceedings 
    in the South African courts to challenge the government's actions. The 
    United States was then joined by other governments from the EU. Their 
    claim, and the claim of the pharmaceutical companies, was that South Africa 
    was violating its obligations under international law by discriminating 
    against a particular kind of patent — pharmaceutical patents. The demand 
    of these governments, with the United States in the lead, was that South 
    Africa respect these patents as it respects any other patent, regardless of 
    any effect on the treatment of AIDS within South Africa. 
    
    We should place the intervention by the United States in context. No doubt 
    patents are not the most important reason that Africans don't have access 
    to drugs. Poverty and the total absence of an effective health care 
    infrastructure matter more. But whether patents are the most important 
    reason or not, the price of drugs has an effect on their demand, and 
    patents affect price. And so, whether massive or mar- ginal, there was an 
    effect from our government's intervention to stop the flow of medications 
    into Africa.
    
    By stopping the flow of HIV treatment into Africa, the United States 
    government was not saving drugs for United States citizens. This is not 
    like wheat (if they eat it, we can't); instead, the flow that the United 
    States intervened to stop was, in effect, a flow of knowledge: information 
    about how to take chemicals that exist within Africa, and turn those 
    chemicals into drugs that would save 15 to 30 million lives.
    """

https://archive.org/stream/free_culture/freeculture_djvu.txt