Because my friend, React generates the virtual DOM during initialisation state (when your app starts) and after that, it directly refers to this virtually saved DOM tree to make changes to the actual DOM. Hence there is no interaction between the two. Hence any change to the DOM by external factors ( J funking Query ) will not be registered by react. React achieves it's speed by reducing reads from DOM as much as possible hence direct DOM manipulation is a big NO NO in react workflow....
If you want me to explain why react avoids reading from DOM, ask me...