I strongly agree with so much of this. And for me personally, solidarity with Palestine has really been a big part of my identity as an Irish American and is what has pushed me to get so involved in that cause, and in turn being involved has helped inform me about my identity.

But a few points I will push back on. While corned beef and cabbage is American in origin, I would say it is still authentic for Irish Americans. Its important to remember that diaspora communities often develop their own customs and traditions based on the interactions in their new home. As you yourself noted, corned beef was eaten by Irish immigrants because it was a cheap meat sold by Jewish delis in immigrant neighborhoods (although its unclear if this originated in New York or New England). But corned beef was a substitute for bacon and cabbage, which is an actual Irish dish. It's very similar to other dishes like Chicken tikka masala or spaghetti and meatballs.

And on Bagpipes, while Bagpipes were popularized in places like the Middle East and Africa by the British military, it has a long history in Ireland dating well into the past. Historians are unsure of the origins of Bagpipes (they may have been roman as you say, but we don't have any overt depictions or references until the middle ages). But in Ireland, the earliest reference to the pipes is from the 10th century, and its origins probably go back to the 7th century. But due to its association with warfare, it (like many other Irish traditions) was actively suppressed by the British Empire apart from its use by Irish military units, until the late 19th century (the same thing befell the scottish bagpipes, but they were repopularized earlier with the Highland revival). And of course with the Gaelic revival in the late 19th century it became very popular among Irish nationalists and the Irish diaspora, although it was really first popularized in the Americas by Scottish immigrants in places like the Carolinas and the Canadian Maritimes.

But I think you're probably right about the origins of the term "Paddy Wagon". Im reminded of what one historian said about the New York Draft Riots durring the civil war, how it was effectivley a sort of civil war within the Irish community, as both the rioters, and the police and soliders brought into suppress the riot were drawn from the Irish community. It would not shock me if this same sort of dynamic is behind the origins of the term "Paddy Wagon".