Analysis-Why are Armenia and Azerbaijan fighting again, and why does it matter?

A still image from video, released by the Armenian Defence Ministry, shows what it said to be Azerbaijani service members moving along an unidentified mountainous border area with Armenia, in this still image taken from handout footage released September 13, 2022. Armenian Defence Ministry/Handout via REUTERS

TBILISI (Reuters) - Several dozen Armenian soldiers and an undisclosed number of Azeris were killed on Tuesday in the deadliest fighting between Azerbaijan and Armenia since a 2020 war.

WHAT ARE ARMENIA AND AZERBAIJAN FIGHTING OVER?