American soldier bumped into non-drinker at one with Italian futurist (9)

'american soldier bumped' is the definition.
I know nothing about this answer so I can't tell whether this works.

'non-drinker at one with italian futurist' is the wordplay.
'non drinker' becomes 'tt' (abbreviation for teetotaller).
'at' means one lot of letters go next to another.
'one' becomes 'i' (Roman numeral).
'with' means one lot of letters go next to another.
'italian futurist' becomes 'marine' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'tt' next to 'i' is 'tti'.
'tti' put after 'marine' is 'MARINETTI'.

'into' is the link.

Can you help me to learn more?