corridors of power

Nor was the Nazi regime, in a time before its concentration camps and wartime atrocities, seen in such a monstrous light. It commanded sympathy within the corridors of power in Britain and in the United States, which was even more aggressively trying to avoid Europe's simmering maelstrom than the British under Chamberlain. - In defense of Neville Chamberlain

this is The Washington Post

It commanded sympathy within the corridors of power in Britain and in the United States - this is in 1938, after The Nuremberg Laws were introduced in 1935

see also @ prof-yura

also here:

At the beginning of 1938, most English people sympathised with German grievances, however much they disliked Hitler’s way of voicing them. The Sudeten Germans had a good case: they did not possess national equality, or anything like it.