Matot 5779. Empathy and Unity

When the Tribes of Reuven and Gad request to settle in the TransJordan, Moses is incensed. He levels two accusations:
1. Shall your brothers go to war, and you stay here?" 2. Your reticence to enter will discourage and demoralize the nation from embarking upon the conquest of Canaan.
The first argument is moral.
The second argument is pragmatic.
The second is concerned that the decision of Gad and Reuven is likely to ruin national morale thereby sabotaging the collective entry to the promised land.
But what of the first? Moses is establishing a fundamental rule of Jewish unity; that no Jew may remain passive, placid, unconcerned, apathetic, when another sector of the Jewish people is in distress.
Rav Soloveitchik expresses it in the following manner:
"A feeling of empathy is a basic fact in the consciousness of shared Jewish fate. The suffering of one segment of the nation is the lot of the entire community. The scattered and separated people mourns and is consoled together.