Being unconditionally proud of the country of your birth means getting the seat in the middle row and claiming that it has the most spectacular view that anyone in the entire plane has.
Which country you are born in is as arbitrary as an unbiased teacher allocating seats on the plane. In that case, if you are born in a country that is not good at something, but you decide to stand up for it just because you were born there then you are fooling no one but yourself.
One should glorify or villify one's country based upon the logical/ethical/moral reasoning and not because one was born or not born in that country.
Here are some great quotes on the subject:
Patriotism is your conviction that this country is superior to all other countries because you were born in it - George Bernard Shaw
A nation is a society united by a delusion about its ancestry and by common hatred of its neighbours - William Ralph Inge
It is not easy to see how the more extreme forms of nationalism can long survive when men have seen the Earth in its true perspective as a single small globe against the stars - Arthur C Clarke
Can anything be stupider than that a man has the right to kill me because he lives on the other side of a river and his ruler has a quarrel with mine, though I have not quarrelled with him? - Blaise Pascal