Definitions of patriotism proliferate, but in the American context patriotism must involve not only devotion to American texts (something that distinguishes our patriotism from European nationalism) but also an abiding belief in the inherent and enduring goodness of the American nation. We might need to change this or that policy or law, fix this or that problem, but at the end of the day the patriotic American believes that America is fundamentally good as it is.
It's the "good as it is" part that has vexed many on the left since at least the Progressive era. Marxists and other revolutionaries obviously don't believe entrepreneurial and religious America is good as it is. But even more mainstream figures have a problem distinguishing patriotic reform from reformation. Many progressives in the 1920s considered the American hinterlands a vast sea of yokels and boobs, incapable of grasping how much they needed what the activists were selling.
Why "must" it involve such echoes of state religion (i.e., fascism)? No one knows. Goldberg doesn't bother to say.