Tank too hard, perhaps, for a US state (5,6)
I believe the answer is:
north dakota
'us state' is the definition.
'North Dakota' can be an answer for 'state' (North Dakota is an example). I'm not sure about the 'us' bit.
'tank too hard perhaps' is the wordplay.
'perhaps' indicates anagramming the letters.
'tank'+'too'+'hard'='tanktoohard'
'tanktoohard' is an anagram of 'NORTH DAKOTA'.
'for a' is the link.
Can you help me to learn more?
(Another definition for north dakota that I've seen is " US state on Canadian border".)