Which preposition to use with counterstroke

by Occurrences 1%

During the third he was defending Canada from American attack and aiding the British counterstroke by every means in his power.

of Occurrences 1%

But this has been France's month, the month in which the miracle of the first battle of the Marne has been equalled by the second, and the Germans have been hurled back across the fatal river by the tremendous counterstroke of General Foch.

Which preposition to use with  counterstroke