The way Cowley uses the phrase "my own country" is an example of

In the context of the poem it could be repetition, but in the context of the content it shows a nationalistic leaning, basically saying that his country is no better in its physical shape but because of the people there it is greater than any other.

The way Cowley uses the phrase "my own country" is repetition.

If you read the poem you will realize that he repeats the phrase "my own country" many times.