The first Śloka sets the saga on the field of Dharma.
Dharma is how we respond, whatever the situation,
presuming we can sustain our view within the present.
Karma is how we respond, having lost sight of our view,
because it’s become obscured by the force of our memories.
Then Karma is the force now driving us through our memories.
So, Arjuna’s Dharma becomes obscured because of his Karma.
– Paul Harvey on Bhagavad Gītā Chapter One verse 1