The fordney-mccumber act, emergency quota act, and rejection of the league of nations are all examples of what growing sentiment?

These three policy actions were all examples of growing American isolationism in the post-WWI period. After the heavy toll enacted by the War, many Americans wanted little to do with entangling world affairs, and the actions of politicians in passing these sorts of measures greatly reflected that sentiment.

They are all examples of growing isolationism.

After the the WWI there was a sense among many Americans that there was nothing gained for their intervention in the WWI. They wanted to distance themselves from the political bickering of the European nations and these three actions are the result of those wishes. This unfortunately lead to the weakening of the League of Nations and increased aggression of the future Axis states.