Not at all. Nationalism will be to the 21st century what fascism was to the 20th.
Nationalism serves to create even more defined in-group/out-group dynamics than what currently exist. This is fundamentally divisive of populations, and with scarce natural resources, arable land, etc, this leads, and will continue to lead, to significant armed conflict.
This can be avoided if one's "nation" defines itself in an inclusive manner, as opposed to an exclusive one. However, this is *rare*, if not nonexistent.