Encouragement brought by an American leader? (5)

I believe the answer is:

cheer

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'encouragement' is the definition.
(I've seen this before)

I can't explain the remainder of the clue.

(Other definitions for cheer that I've seen before include "Hearten; shout" , "Applaud with shouts" , "Perk up" , "Buck up" , "sound of appreciative audience" .)

I've seen this clue in the Evening Standard.

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