Conversation so far:
when is a flag flown at half mast
In the United States, the President can issue an executive order for the flag of the United States to be flown at half-staff upon the death of principal figures.
when did the tradition of lowering the flag at half mast start
The tradition of flying the flag at half-mast began in the 17th century.
why is it lowered to half mast
According to some sources, the flag is lowered at half mast to make room for an invisible flag of death flying above.
does italy follow the tradition of lowering the flag at half mast
The flag of Italy was flown at half-mast after the 2013 Sardinia floods on 22 November 2013.

Question: how about japan
Self-contained rewrite: does japan follow the tradition of lowering the flag at half mast