The scene is set as the two heads of completely opposed nations (Yaakov and Esav) meet each other for the first time since Yaakov got his bracha from Yitzchak. Before this meeting, Yaakov davens to HaShem to 'please save me from the hand of my brother, from the hand of Esav (32;12).' Why repeat things (why repeat things!) by saying 'the hand of my brother' AND 'the hand of Esav?'
An answer is that these two concepts ('my brother' and 'esav') represent the 2 tactics employed against us as individual Jews and as the Jewish people as a whole. One is the enemy who overtly
and obviously comes against us by force to annihilate us (that is called 'esav' -the obvious enemy) anti-semitism. The other is much more dangerous, and that is 'achi' - my brother.
This is when our destruction is caused via nations pretending to be our friends/brothers in behaving liberally to us and watching us self-destruct; assimilation. [And we have lost much more Jews to the 'achi' type of enemy than the 'esav' type/]
Thus, Yaakov was davening to be saved not only from the physical force/danger of Esav, but also from the influence of Esav his brother should Esav decide to behave kindly to him.
The lesson? to notice that just as we face physical dangers, one must not forget to arm ourselves internally to fight off the spiritual dangers too. .