The most common and most likely answer to this crossword clue is the 8 letter word CHEROKEE
I've seen this crossword clue in The Times
C
H
E
R
O
K
E
E
More clues leading to the result CHEROKEE
- Romantic hero keen to hide American
- Brave of Nancy’s dear old chief to speak out
- Brave Nordic hero keeping near the centre
- Brave, brave man passing through outskirts of Cannock with ease, they say?
- Conservative idol largely enthusiastic or one found with reservations?
- OK, cheer set point for the brave
- Early American rustic hero keeping masks
- Old American Conservative hero’s not entirely eager
- Native American protagonist living mostly under cover, initially
- Indian film star reportedly critical after onset of cancer
Buddy explains!

The straight part
We know that "American" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case american = cherokee.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.