you mixed the query with the register function, try this:
function taxonomy_init() {
// create a new taxonomy
register_taxonomy(
'country',
'post',
array(
'label' => __('Countries (Labels)'),
'rewrite' => array('slug' => 'location')
)
);
}
add_action( 'init', 'taxonomy_init' );
the in your query use
$my_query = array(
'posts_per_page' => 10,
'tax_query' => array(
array(
'taxonomy' => 'country',
'field' => 'id',
'terms' => array(4)
)
));
since you are querying only one term you don’t need to order by term_id.
if you are trying to achive something else the please explain a bit more.