Final answer:
It would be useful to find information before and after 9/11 when comparing attitudes towards travel.
Step-by-step explanation:
When comparing attitudes towards travel before and after 9/11, it would be useful to find information from both time periods. The terrorist attacks on September 11, 2001, had a significant impact on travel and public perceptions. Studying data before and after 9/11 would help identify any changes in attitudes towards travel related to safety, security, and perceptions of different cultures or ethnicities.
For example, research by the Pew Research Center has shown that public opinion about Muslims became more favorable after 9/11 due to efforts by President Bush to discourage blaming Muslims in general for the attacks. This indicates a potential shift in attitudes towards religious and cultural tolerance.
Therefore, considering information before and after 9/11 would provide valuable insights into how attitudes towards travel have changed and the impact of the terrorist attacks on public perceptions.