Braindrain:
I can't speak to the motives of others but in my case what you describe as anti-Americanism is actually anti-militarism and anti-imperialism. These themes were expressed by many fiercely loyal Americans including your first president, George Washington, in his departing letter to the American people after his second term as president, by Thomas Jefferson, by James Madison, and later by famous members of the Anti-Imperialist League such as William Jennings Bryan and the popular humorist and fervent anti-imperialist Mark Twain (aka Samuel Longhorn Clemens). I will include a link to a famous essay written in 1901 IIRC by Twain regarding the emergence of US imperialism and the use of militarism to back up that new colonial project undertaken by America after 1898 on foreign shores.
https://shsamstud.pbworks.com/f/To+the+person+sitting+darkness.pdf
One need not be anti-Americcan to be a critic of American imperialism and American militarism in the 20th and 21st centuries. Sometimes the best friends you can have are the ones who will speak blunt truth to you even when the truth is the last thing you yourself want to hear. So feel free to cast aspersions on me and my motives if you so wish. I know why I say the things I do and why I speak publicly about them and they are born out of a love and respect for the USA, its people and its "small-r" republican traditions which are being trampled underfoot by militaristic imperialists today.
My mum was a US Army nurse from 1942-1945 and she was stationed in Britain, in France and later in Germany during and immediately after WWII. She was fiercely proud of her country and her fellow countrymen but she was also unable to accept the corruption and institutional violence which came with de facto empire by her country. When she returned to New York after the war she was both a vehement anti-communist and an equally vehement anti-imperialist, because she saw no real qualitative difference between the motives and means of both the Soviet and American empires, except for the flavour of their rhetoric. She hated the communists more because of their open disregard for killing and displacing millions in the pursuit of their empire but also despised American militarism and imperialism for the millions it made miserable, impoverished and killed both directly and indirectly.
So think what you will about me and why I say what I do. I can't change peoples' minds who are so deeply invested in their own militarism, imperialism and exceptionalism that they are blind to others' visions of what is going on. However other viewers here may read, think and begin to understand my point of view and become a little more aware of the bill of goods which they are being sold daily by cynical politicians, bloody-minded militarists and hawkish military officers in the service of imperialism and maintaining the multi-faceted hegemony of the post-WWII Grand Area Doctrine.
Perhaps you yourself could take some time and read Mark Twain's scathing and satirical essay on US policy regarding the Boer War, the Chinese Boxer Rebellion, the Spanish-American War, the Moro War and the crushing of Filipino independence by the nascent US Empire at the dawn of the 20th Century. Even if you reject it, it is always better to study and understand your potential enemy, in preparation for the inevitable engagement between you both.
Cheers.
Evilroddy.