The most common and most likely answer to this crossword clue is the 6 letter word LAGGED
L
A
G
G
E
D
More clues leading to the result LAGGED
Buddy explains!

The straight part
We know that "Was behind/given protection" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case was behind/given protection = lagged.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.
What does LAGGED mean?
LAGGED verb- To fail to keep up (the pace), to fall behind
- To cover (for example, pipes) with felt strips or similar material (referring to a time lag effect in thermal transfer)
- To transport as a punishment for crime.
- To cause to lag; to slacken.