What does the cryptic crossword clue "Troops soon need to be treated very close at hand (2,4,8)" mean?

The wordplay uses an anagram. anagram of TROOPS + SOON + NEED = ONONESDOORSTEP The answer is ONONESDOORSTEP.

Troops soon need to be treated very close at hand (2,4,8)

Daily Mail Cryptic #17327 | 8 Down | 2024-04-02 flower