Clue: Sodium converted into alumin­ium is helping right away with public ownership (15)
Answer: NATIONALISATION
Explanation: Definition: public ownership
A charade of NA (chemical symbol, 'sodium'); plus TION, an anagram ('converted') of 'into'; plus AL (chemical symbol again, 'aluminium'); plus 'is'; plus [r]ATION ('helping') minus the R ('right away').