Why do Bees fight against the Japanese Giant Hornets when they'll get slaughtered

whenever the Japanese Giant Hornet finds a bee hive they attack it and call more hornets to join the fight. and 30 of these Hornets are known to slaughter 30,000 European honey bees. The Japanese Hornets always win against the bees unless it's the Japanese bees. Why would the bees fight these hornets in the first place don't they know they'll murdered?
and if the bees retreat their hive it'll spare their lives and they can build a new hive somewhere else

Becaue bees are brave, and will fight with their lives to protect their hives from these sinister Hornets or anyone. bees will fight anything that threatens there hive.

european honey bees evolved where there were no hornets so have no defense against them.

bees do not know they will die, they sting as a defense and die when they try & remove the sting.
They are quickly replaced.