We are saying this is the result of allowing the distinction to exist and openly supporting it even in government. These Turkish protestors would be a lot fewer if the distinction didn't exist. Look at America, everyone is American regardless if race or ethnicity. Once you get your citizenship, you are an American an no one has the right to call you anything else.
We have to fully embrace progressivism, and equality. The notion of 'allochtoon' is poisonous, and just as it harmed minorities in the netherlands, it will harm the whole of the netherlands over time (as it is doing right now).
It's actually the complete opposite. The policy to not see any difference between natives and people with a foreign background is what has created this mess. If you act like everybody is the same you're not having policies in place to make that happen.
What you're saying about the US is very true, and they don't get enough credit, for how thorough they are in nation-building and integrating new citizens. They have a strong cultural identity and expect people to become part of that and be proud of it.
When Turks were brought into the Netherlands for cheap labor they were specifically exempt for having to integrate with the idea that they would go back after a little while. When that idea changed the policy should have adapted: A program should have been put in place to give people the foundation to succeed in the Netherlands, that included not only language but also cultural values, they had to take part in before they were allowed to bring over a Turkish partner and start a permanent live here.
We failed on two fronts - people not wanting to integrate we did not care about and let them, and people who wanted to integrate we had nothing to offer.
And still today, there are many people with foreign backgrounds with a mentality that will only ever set them up for failure and/or crime, and even poor health. When you say 'everybody is dutch' that doesn't make it so. You need policies to transform these people into actual dutch citizens, and actually forcing them to make a choice between the country they live in and the country of their ancestors is an important first step. Creating programs that impart western values like respect for women, gay people and a desire to take constructive part in community, in addition to western work ethic would be a next step. You could link these programs to social programs to have people take part in them, so that the also large group of foreigners that simply work aren't bothered by it.