Seriously?
WWII
The Marshall Plan
Norman Borlaug (I think they say there are 0.5-1 billion extra people in the world thanks to Borlaug, which is a lot of suffering averted.)
Technology - the suspension bridge, the light bulb, photographic film, the skyscraper, the airplane, much of computer technology, much of automotive technology, much of medical technology, nylon, the microwave oven, integrated circuits, lasers, LED lighting, fiber optics, GPS, the internet, credit cards.
I'm pretty sure the only way you can rank nations by their philanthropical contributions and not have the US come out on top is to divide by GDP (not population) which says more about Wall Street than how great Americans are.
Yes, lets skip the annihilation of the native population.
Hiroshima/Nagasaki
Hell, even the fire bombing of Tokyo killed more than either Hiroshima or Nagasaki.
Lets include bombing of Dresden. 20k+ civilian deaths, many of whom fled the GREAT RAPE coming from the east.
Division of Korea into North/South and the subsequent civil war.
After US forces took most of Korea, China intervened in the war. They wanted their seat on the security council instead of Taiwan a little island where the Nationalists took refuse after losing the civil war.
Multiple US backed coups in Cambodia which eventually lead to the Khmer Rouge taking power after country was left in massive chaos.
Congo - supporting overthrow democratically elected government in Congo and killing its leader leading to decades of war and instability
Persia (Iran) - overthrow of democratically elected government to install a dictator. Dictator was overthrown in 1979, US immediate response is to provide weapons and intelligence to their good friend Saddam to invade. Lets forget that little incident where US navy illegally entered Persian waters and "accidentally" shot down a civilian air liner.
Provided weapons, training, money to the Mujahadine largely via Pakistani intelligence including elements that would grow into al-queda.
US also backed the military coup against the democratic government of Syria in the late 1940s.
Its been almost 15 years, did you find justification for invading Iraq? Right.... I'll wait another 15 years.
The irrational and absurd embargo of cuba. Lets skip over the part when fighting in Cuba against the Spanish their independance was promised and never delivered.
I mean there is many many many many many more examples.