Nationalists are a person with strong patriotic feelings, especially one who believes in the superiority of their country over others.
Patriots are a person who vigorously supports their country and is prepared to defend it against enemies or detractors.
They re similar in the way that they both support their country greatly.
They are different because nationalists think their country is better, while patriots will fight for their country no matter what happens. Patriots know that their country isn't "better" per say, but they will protect it.
