there were several , although the Vietnam war was the worst by many people estimation.
Between 1850 and 1860, the three presidents considered to be among the worst in American history were Millard Fillmore, Franklin Pierce, and James Buchanan. Buchanan is often considered the worst of all.
england
Three Mile Island, Pa, 1979
1925. There were 794 tornado deaths in the U.S. that year, 695 from a single tornado.
They are considered some of the worst man-made environmental disasters in U.S. history.
eastland disaster
Chernobyl
The worst accident in history is considered to be the Chernobyl nuclear disaster that occurred in 1986 in Ukraine. The consequences of the accident included the release of a large amount of radioactive material into the environment, leading to widespread health issues, environmental contamination, and the displacement of thousands of people from their homes. The long-term effects of the disaster are still being felt today.
As the worst disaster in their military history; which in actuality it may have been their first military disaster in Japanese history.
It is difficult to pinpoint the "worst" disaster as each one is unique in its impact and consequences. Some of the most devastating disasters in recent history include the 2004 Indian Ocean tsunami, the 2010 Haiti earthquake, and the 2011 Fukushima nuclear disaster. Each of these events resulted in significant loss of life, widespread destruction, and long-term environmental and social consequences.
Hurricane Katrina was considered the worst natural disaster in US history due to the widespread destruction it caused in New Orleans and along the Gulf Coast. The response to the disaster was criticized for its slow and inadequate efforts in evacuating residents, providing relief, and managing the aftermath, leading to loss of life and prolonged suffering for many affected individuals.
Since you have used the word "disaster" meaning widespread destruction and distress, I would have to say the terrorist attacks on 9/11 to the World Trade Center would be considered the worst aviation disaster that led to about 2,800 deaths. The worst aviation accident, would be the Tenerife disaster was the worst to 747's ran into each other 03/27/77 there were 583 fatalities.
The worst aircraft accident in history was definitely, in my opinion, the Tenerife airport disaster. It was very morbid what with all the deaths. Want more info? Go to wikipedia and search it.
The Cyclone Mahira in 1899 was the worst natural disaster in Australia.
The Senghenydd mining disaster occurred on October 14, 1913. It was the worst mining accident in British history, resulting in the deaths of 439 miners.
The Chenobyl Disaster was a nuclear accident that occured on 26 April 1986 in Ukraine, when a nuclear reactor exploded and gave hundreds or thousands of people radiation poisioning. It killed a number of people, too. The nearby city of Pripyat had to be evacuated entirely, though some people who wanted to stay did so illegally. It is considered the worst nuclear disaster in history.