Comment by datsci_est_2015

Glad you asked!

Perhaps I should have used the term “sovereign state”, as that’s more precise, even though when most people use the colloquial term “nation” (as in “nationalism”) they’re referring to a sovereign state.

A sovereign state has borders they can enforce to their own discretion (political gridlock notwithstanding), a stable and well-defined (non-transient) population, a single recognized government (both internally and externally), and ability to conduct foreign relations without being stopped by force or decree.

So, with that more precise definition out of the way, you can recognize that the flags in your links do not represent sovereign states, but rather peoples - who, coincidentally, are often fighting for their rights and freedoms.

Elsewhere in the thread are mentions of nation flags, like the Union Jack, which represent a sovereign state, and are instead often associated with national identity, xenophobia and oppression.

Hope that helps!