National Identity items:
  1. Being American is an important part of my identity
  2. I like to see myself as an American
  3. I feel connected to the American people
Possible responses range from Strongly agree (1) to Strongly disagree (9).
Source:
Baray, G., Postmes, T., & Jetten, J. (2009). When I equals we: Exploring the relation between social and personal identity of extreme right‐wing political party members. British Journal of Social Psychology, 48(4), 625-647.