I'm trying that out, and it seems that jquery is installed when you include the Semantic UI CSS. According to the docs: http://react.semantic-ui.com/usage, you need to install the CSS separately with
$ npm install semantic-ui-css --save
and with that I get
├─┬ semantic-ui-css@2.2.10
│ └── jquery@3.2.1
Plus a whitescreen because jQuery is not defined...bummer