Europe is of course defined by the ECHR rights to life, liberty, and so on. This does not include "the pursuit of happiness" but it's not really clear how the school shootings help with that.

First, Europe is not a country.

Second, the ECHR mainly concerns itself with the "duty of states" to protect life, not the people's right to life itself.

Here is Article 2: https://en.wikipedia.org/wiki/Article_2_of_the_European_Conv...

It is relatively recent that courts have even rules on this, primarily with McCaan v UK

https://en.wikipedia.org/wiki/McCann_and_Others_v_United_Kin...

In the US, the right to life and liberty supersedes the right to safety. Based on the founding documents, Americans, because they are HUMANS, are born with the right to protect their lives and to pursue happiness. There is no right to safety (as there is no "RIGHT TO HAPPINESS") as safety would be something that OTHERS would have to provide YOU. Nothing that others must provide you can be a right.