No longer. For a generation the melting pot has been double-plus ungood crimethink. The "Salad Bowl" is now what our moral and intellectual superiors favor. Each group (never individuals, always groups) remain their own non-American identity as they are tossed together with other diverse groups. And what we see from this is that the trust required to keep a single society functioning is breaking down.
The Democratic Party's coalition requires a set of victim groups to give it political power. As a result, their favored policies have tried to inhibit the melting pot and reinforce group differences. Minorities are penalized from diverging from accepted behavior for the group - "don't act so White", that sort of thing.
And so the feeling that we're all in this together that was so common in my youth is pretty much used up. The question is, what comes next?
I think that this road that we are on leads to secession. We've already seen a geographical divergence of governance, with Blue states increasingly pushing the Salad Bowl grievance identity politics (limited growth with government distributing the jobs) and with Red states pushing pro-business, pro-growth politics (i.e. melting pot with enough jobs to go around). This will not continue forever: a middle class increasingly under financial pressure will flee the Blue states, increasing the fiscal strain that those governance models experience. At some point the Blue states will demand to be bailed out en masse, and the Red states will refuse.
At this point the split will occur. I expect it will happen within my lifetime.
We face a crisis of governance, a crisis of trust, and a crisis of philosophy. Political groups have gotten ahead by fostering these crises: public sector unions with unsustainable pension benefits, race baiting politicians always pushing the "raciss" line, and a post modern university where racism can only come from whites (even, or perhaps especially, if they are poor). These groups will not try to heal the split; indeed, they have every incentive to make it worse. The "us vs. them" of the salad bowl will see to it that the greens up and leave to a different table, just because they're tired of hearing the carrots tell them what a bunch of bigots leafy vegetables are.
Notice that none of the typical "culture wars" issues will be the driver of this split, it's all the economics of bailout. Where a bailout might have been possible in a higher trust melting pot environment, the bank of social capital will have been exhausted. Long simmering resentments will flare in the strained fiscal environment and suddenly both sides will realize that a divorce will be a relief.
It a massive tragedy of the commons, as the Democratic party squanders the communal capital built up over 200 years. In the span of 50 years it will all have been used up, and the polity will splinter. The irony is that the parts left with the Democrats will look a lot like Europe, but not in the good way of fancy aristocratically commissioned architecture with great food and wine; rather, a society of General Strike, zero job growth, and capital flight.
Damn, I'm sure glad I got out of Massachusetts before they built a Wall.
The North has used the doctrines of Democracy to destroy self-government. The South applied the principle of conditional federation to cure the evils and to correct the errors of a false interpretation of Democracy...[and the inevitable result of an unfettered federal government will be] the initiative in administration; the function of universal guardian and paymaster; the resources of coercion, intimidation, and corruption; the habit of preferring the public interest of the moment to the established law; .............. a public creditor; a prodigious budget these things will remain to the future government of the Federal Union, and will make it approximate more closely to the imperial than to the republican type of democracy.
- Lord Acton, correspondence to Robert E. Lee