Answer:
During that time period of WW1 and 1929, there was a lot of changes occurring for America including:
- Women's fight for suffrage
- American's military entering the war
- And the effect of isolationism due to the war
America didn't desire to go into any conflict after World War 1 and emphasized the ideal of isolationism.
You can infer that timespan was negative due to the damaging effects WW1 brought to America, however you can also highlight Women's suffrage as being a positive impact.
I recommend, as I've done above, create a bullet list of all the pros and cons of that happened to America during that timespan. Then choose which one was the most impactful (either being positive of negative) and create your response off of that. You can also incorporate the other factors during that time period to help support your response.