Social media can whip people into a frenzy and create a tyranny worse than what the government can do because there is virtually no accountability. The court of public opinion doesn't let you appeal your sentence.
https://www.merriam-webster.com/dictionary/nationalism
> loyalty and devotion to a nation especially : a sense of national consciousness (see CONSCIOUSNESS sense 1c) exalting one nation above all others and placing primary emphasis on promotion of its culture and interests as opposed to those of other nations or supranational groups
1. The refugee crisis that Germany brought in not only on itself but on the rest of the EU.
2. The same Germany has recently spearheaded a trade deal with the devil.
Germany used nationalism for the wrong reasons (short term gain and long term pain)