Warfare and weapons systems

Occasionally I read books or watch films about historical events and periods to learn - or remind myself of lessons I have already been aware of. I've just done that with a film about the development of the atomic bomb. 

That is a truly awful weapons system - one that still, as of this instant, has the active potential to destroy human civilisation and much of all life on the planet within a matter of hours (the Doomsday Clock is set at 100 seconds, but the actual launch and travel times in a nuclear war would be up to a few hours, with effects such as a "nuclear winter" creating disaster for years afterwards). 

There are, however, other awful weapons systems - or systems that have seemed awful at the time. These include: 

• anything which increased human impact (stone weapons and swords, for instance) or projected conflict beyond arms reach (such as spears or bows and arrows); 
  
• chariots; 
  
• Greek fire; 
• cavalry; 
• catapults; 
  
• gunpowder weapons including artillery; 
• machine guns; 
• mines; 
  
• chemical weapons; 
• weaponizing aircraft; 
  
• biological weapons.
  

When watching films such as the one I just have, it is easy to focus on the behaviour of those directly involved - particularly those who are so focused on intellectual challenges that they act without ethics. True, those people are unbalanced or even unscrupulous, but they cannot operate, let alone be effective, on their own. 

Take the Manhattan Project, for example. That employed up to 129,000 people, mostly (around 126,800) in construction or support industries (suggesting likely hundreds of scientists in the other 2,200 people), and cost something like US$1.9 billion at the time (current equivalent $21.7 billion). Successfully changing the hearts and minds of a few key people may have delayed the project, but is unlikely to have stopped it. 

Changing the hearts and minds of key decision makers like President Truman - which I consider an impossibility - would have made a difference, and that leads into the point I wish to make here:

Preventing evil is not best done by changing one or a few people (let alone the inherently flawed means of trying to assassinate an evildoer, which only create martyrs and taints the resultant end - although assassinations have been used with devastating effect against those in a position to do good, such as Yitzhak  Rabin, which destroyed the Oslo Accords), but by a robust and properly informed discussion by society which reveals and heals flaws (such as ethical blindness, whether from small-mindedness/xenophobia or the human desire for loved ones to come home safely from a war, active anti-ethical behaviour such as bigotry or other forms of hate, or just lack of awareness/knowledge such as the implications/consequences of courses of action) and enables society to commit itself to constructive action - such as the abolition of slavery in the UK in the early 1800s or (mostly northern) USA in the 1860s, or the banning of chemical and other weapons and other  problems (or potential problems) and atrocities in the various Hague (and other) Conventions (although some apparent gains, such as banning  expanding [aka "dumdum"] bullets, were actually to reduce the cost of wars).

Achieving that can take decades and be exhausting for those actively involved (e.g., see here, here, and here), but the wars, conflicts and other problems that result from not doing that is worse for society as a whole.