I think this is what you want…
This isn’t tested so you may have to fiddle with it.
in your functions.php
file, add something like this :
EDIT (2)
After rereading, I saw you’re not using custom post types, so i’ll change my code accordingly. I don’t know how to detect when you’re on the ‘manage all posts’ page, so maybe someone can complete my 'if'
statement.
This should work.
function set_post_order_in_admin( $wp_query ) {
if ( is_admin() ) {
if( 'edit.php' === $GLOBALS['pagenow'] ) {
$wp_query->set( 'orderby', 'menu_order' );
$wp_query->set( 'order', 'ASC' );
}
}
}
add_filter( 'pre_get_posts', 'set_post_order_in_admin' );