react redux - почему до компонента доходит пустой state?

// roorReducer
import {combineReducers} from "redux"
import {headerReducer} from "./headerReducer"

export const reducer = combineReducers({
    header: headerReducer,
})

// headerReducer
const initialState = {
    routes: [
        {to: '/', text: 'Главная'},
        {to: '/catalog', text: 'Каталог'},
        {to: '/partners', text: 'Партнеры'},
        {to: '/reviews', text: 'Отзывы'},
        {to: '/team', text: 'Команда'},
        {to: '/contacts', text: 'Контакты'},
        {to: '/blog', text: 'Блог'},
    ]
}

export const headerReducer = (state = initialState, action) => {
    return state
}

// компонент Header

import React from "react"
import {connect} from 'react-redux'

export const Header = props => {
    return (
        <header className={'header'}></header>
    )
}

const mapStateToProps = state => {
    return state
}

export default connect(mapStateToProps, null)(Header)

// index.js
import React from 'react'
import ReactDOM from 'react-dom'
import * as serviceWorker from './serviceWorker'
import App from './App'
import {Provider} from 'react-redux'
import {compose, createStore} from 'redux'
import {reducer} from "./redux/reducers/reducer"

const store = createStore(reducer, compose(
    window.__REDUX_DEVTOOLS_EXTENSION__ && window.__REDUX_DEVTOOLS_EXTENSION__()
))

ReactDOM.render(
    <React.StrictMode>
        <Provider store={store}>
            <App />
        </Provider>
    </React.StrictMode>,
  document.getElementById('root')
)

serviceWorker.unregister()