As we approach יום העצמאות (Israeli Independence Day), I think of all of the progress that Israel has made since 1948. What started off as a discombobulated nation-state that was barely able to stand on its own metaphorical two feet is now a beacon of democracy and economic prosperity in an otherwise dark abyss of totalitarianism and economic stagnation. Even with Israel's successes, I can't but help think that Israel has not made as much progress with its neighbors as it should have by now. Sure, there's a cold peace with Egypt and the Jordanians are much more tolerant of an Israeli neighbor than during Israel's inception, Israel still has a while to go, particularly with the Palestinians. At least since the Oslo Accords, Israel has sincerely pushed for a two-state solution in which an Israeli state can live alongside a Palestinian state in "peace and harmony." If anything should have confirmed the unfeasibility of a two-state solution, it should have been Gaza attacking Israel as soon as Israeli forces were removed from Gaza back in 2000s. None of this even takes into account the geographic distance between Gaza and West Bank, or the plethora of other issues that come along with creating a single, unified Palestinian state. Since the two-state solution approach is not working, how about a one-state solution?
A lot of the success of the one-state solution would be contingent upon its implementation. First, this one-state solution would be under the authority of the Israeli government, not a Palestinian government. Without getting into detailed comparative politics, Israel is the only one to handle the implementation of a one-state solution. There is also the matter of what Israel would annex. As long as Gaza's democratic representation is based in Hamas, a terrorist organization hellbent on Israel's destruction, I would not integrate Gaza into the annexation of the disputed territories. Gaza has been and continues to be a mess. Upon annexing Gaza during the Six Day War, Israel actually tried giving Gaza to Egypt, but not even Egypt wanted to deal with the headache. There is also the issue of whether to grant Palestinians full or limited voting rights, which would, amongst other institutional protections, act as a buffer to maintain the Jewishness of the State of Israel. Tangentially, I would imagine that a loyalty oath would be a prerequisite of the integration of West Bank's citizens, much like it was back in 1948. Furthermore, there is the issue of whether to grant the Palestinians in the West Bank full citizenship, permanent residency, or something in between (or even the infeasible explosion of Palestinians from the West Bank, which I think is a bad idea for more reasons than one). There are also issues of how to deal with "right to return," which I think would be relatively less contentious under a one-state solution than under a two-state solution.
A major potential impediment is the oft-called demographic time bomb, which is the notion that the Arabic population would procreate at a faster rate than the Jewish population, thereby making the Jews a minority in the Jewish homeland. Before crying "Never again!", we should realize that the demographic time bomb is more of a dud than anything else. I have not read Caroline Glick's The Israeli Solution, but from what I can tell from reviews of her book, she covers the topic pretty well. Israel has precedented success for integrating over one millions Arabs into Israeli society. The State of Israel has been able to maintain the Jewish facet of its national identity while being able to have a fifth of its population be non-Jewish. Even if they absorb those from both the West Bank and Gaza, at best, Arabs would be a third of the population. And if the Arabic birth rate is 2.97 and the Jewish birth rate is 3.50, mathematically speaking, there is no basis to fear a demographic takeover of the Jewish state. To make the integration of Palestinian Territories easier, what the Israeli government can do is grant the territories provincial quasi-autonomy while being under Israeli sovereignty.
With the current stalemate in the Middle East, this is all theory. Miscegenation did not help in the United States, and I don't think the miscegenation inherent within a two-state solution would help with fostering amicable relations between the Israelis and Palestinians. A one-state solution would foster better understating and co-habitation in the long-run, and it would be less likely to alienate Palestinians in Israel than a two-state solution would. Even if you want to say "bi-nationalism works with Northern Ireland, South Africa, or Canada (well, sort of), but doesn't work with places like Iraq or Yugoslavia," the Israeli-Palestinian conflict is unique enough where precedent acts as a tenuous proxy. The right to nationalist self-determination, political feasibility, integrating the new Arabs into the Israeli welfare system, international criticism, and maintaining the legitimacy of Israel being a Jewish state would all be obstacles to the one-state solution. I still strongly believe that Palestinian recognition of a Jewish state is a pre-requisite before either a two-state or one-state solution, or even a three-state solution, takes place. However, if that were the case, I would make an educated guess that a one-state solution would work better than a two-state solution in the long-run.