B’chol dor v’dor omdim aleinu l’chaloseinu
R’ Chaim Berlin asks why the double lashon? It could easily have just said “B’chol dor” (in every genreation).
The reason why it says “dor” twice, is due to the fact that no two generations are the same in terms of their methods and decrees, yet it nevertheless boils down to the same thing.
There are generations in which the Jews are persecuted and tortured with antisemetic laws in an attempt to break our will and our connection to Hashem. The Founding father of this method was Paroh.
There is also an alternative method which uses love and friendship in an attempt to separate us from our service to Hashem (e.g. assimilation). The founding father of this tumah was Bilam.
There is a common denominator “Omdim Aleinu L’chalosaynu” the only difference is the method used to reach this desired goal.
For this we say, i.e. on both of these methods, HaKadosh Baruch Hu Matzilanu M’yadam. Hashem saves us from both types of attacks.