Nothing felt different about America recently (2,4)
I believe the answer is:
of late
'recently' is the definition.
(synonyms)
'nothing felt different about america' is the wordplay.
'nothing' becomes 'O' (O resembles 0).
'different' indicates anagramming the letters.
'about' indicates putting letters inside.
'america' becomes 'a' (common abbreviation - e.g. in organisation names).
'felt' anagrammed gives 'flte'.
'flte' enclosing 'a' is 'flate'.
'o'+'flate'='OF LATE'
(Other definitions for of late that I've seen before include "In the recent past" , "In the past few days" , "Recently, not long agor" , "recently, not long ago" , "Alternative to 21 down" .)