Wars break out around junction in the tube (5)
I believe the answer is:
straw
'tube' is the definition.
(I know that straw is a type of tube)
'wars break out around junction' is the wordplay.
'break out' is an anagram indicator.
'around' indicates putting letters inside.
'junction' becomes 't'.
'wars' anagrammed gives 'sraw'.
'sraw' enclosing 't' is 'STRAW'.
'in the' is the link.
(Other definitions for straw that I've seen before include "Means to absorb" , "Stems left after grain has been removed" , "Remains of corn" , "What a sucker gets given" , "Thin tube; yellow" .)