(note: these are an example from my recent problem/solution collaborations listed on www.borgger.com; the original material for these thoughts is culled from my discussions in the Facebook forum: "Students for a Peaceful, Unified, and Democratic China")
As a teacher living and working in China (PRC), there are three T's that are considered verboten subject matter when teaching the children: Tibet, Taiwan, Tiananmen Square (i.e. democratic reform). Although these are certainly not the only areas of sensitivity to the Chinese people of the mainland, these are matters of primary concern to the CCP (Chinese Communist Party). Taiwan is also a dicey geopolitical problem for the entire region, as well as the US due to its obligations. Here are my own thoughts regarding how this issue may eventually be resolved. Feel free to add to/debate their efficacy!
(1) No politician--except Cincinnatus--in the history of politics has entirely willingly given up his acquired power. It cannot be expected that either the democratically-elected politicians of the RoC (Republic of China) in Taiwan or the authoritarian oligarchs of the PRC (People's Republic of China) would be willing to give up their political domains or share those domains without a pretty major upset of the status quo, most likely one of catastrophic proportions.
(2) The status quo is a foreign policy fiction which states the existence of a single nation called China, despite the foreign policy reality that there are two governments sharing that nation and even giving slightly differing names for that nation--the two governments being the democratic government of the RoC which controls 'Taiwan province' as well as some islands off the coast of/belonging to Fujian province, and the CCP (Chinese Communist Party) which controls all of mainland China, several autonomous ethnic regions, the Special Administrative Regions of Hong Kong and Macau.
3) Current thought in the CCP/PRC favors the extension of the SAR (Special Administration Region) status to Taiwan and its RoC. It already maintains this as a sort of polite fiction that can often be seen in the setup of its special airport concourses lumping flights into the SARs and Taiwan together. This form of SAR would allow for 'one country, two systems' of government, as seen with Macau and Hong Kong, the latter more than the former defending a quasi-democratic form of colonial government that (supposedly) allows for only limited interference in its internal governance by Beijing amd (supposedly) allows for ultimate transition to full democracy--although this transition has already been postponed several times by Beijing in order to preserve a status quo where pro-Beijing representatives in the legislative council enjoy advantage. Given the degree of actual interference by Beijing in Hong Kong's internal matters, and given that the RoC government (with its pretences to be the legitimate government of all China) cannot be equated with the colonial governments of the two SAR city-states,I find it unlikely that the people or politicians of the RoC/Taiwan would find SAR status an acceptable compromise.
3) This brings us back to the apparent necessity of a catastrophe within the overall territory of China in order to change the status quo between the two governments of China/two Chinas.
A lot could be debated about where/how/what potential catastrophe could upset the current status quo in a way that would aid a peaceable transition from two governments occupying that nation to some manner of unity. Various prognosticators envision natural disaster, man-made disaster, or revolution stemming from CCP mismanagement of China.
While no one can really know the future, I don't see these as events to be hoped for, not least because of the damage to China itself and danger to the lives of the Chinese people. I also don't find the last option all that likely, especially as long as the army is firmly loyal to CCP policy. For one thing, the current generation of Chinese youth is notable for its self-indulgent (xiao huang di, or 'little emperor syndrome') behavior, and thus it is unlikely to see much growth in attitudes for change among the middle class--at least enough so to truly endanger the CCP's privileged position in mainland Chinese society. Of course the CCP itself seems to be playing with fire when it encourages Chinese youth in recent displays of hyper-nationalistic attitudes; it cannot be certain how long such passionately patriotic youth will put up with leadership from aging CCP dinosaurs with whom they have little in common.
Other posible vectors for internal societal change could come from the increasing discontent of the country's rural majority, or its increasing numbers of urban migrant workers who are not fairly too well in the current global economic downturn. It remains to be seen whether any effective leadership or capability to strike at the country's leadership could emerge from such a quarter. Historically, China has often managed to do just this.
In any case, as said previously, such violent ends to the current status quo are probably not anyone's first preference.
4)The needed change, therefore, seems most likely to come from within the CCP itself. The current arrangement of the Party, after all, has almost nothing to do with Communist ideology, and everything to do with the powerful maintaining their position at the center of a vastly self-enriching web of guanxi (personal favors; corruption). So what argument could possibly persuade such people to put their position and access to personal wealth in the hands of popular mandate? The only situation would be one where political insiders are contesting rival factions for access to China's official and unofficial taxes.
It is apparent now that there are at least two main factions, possibly more, and certainly several minor factions as well, all contesting for power within the insular CCP (note, recent reprisals against Jiang Zemin's 'Shanghai faction'). It is possible that the contest could eventually spill outside the bounds of the party, and one or both factions would need to resort to having their power claim validated by popular or military mandate.
IF such happened, it might also be possible to see an alliance between one or more former CCP factions with RoC (and HK) political parties. Taiwanese politicians are unlikely to rejoin the mainland unless they can both retain benefits of their current position, and acquire a piece of the national pie. As for the mainlander party, whoever can successfully negotiate the reunification of Mainland and Taiwan would have won a great prize indeed, enough to fuel a popular (democratic) mandate. The mainland military might not appreciate being bipassed to achieve that goal, however, and it is hard to determine exactly what role they might play in all of this.
Finally, I don't imagine that this will come to pass in the immediate future. It could take fifty years or more, quite easily, for the opportune moment to arrive. Even in the current economic crisis, China does not seem to be one of the worst hit, and the current regime can probably manage to squeak past, even if discontent among the migrant workers recently unemployed increases.
Patience is the key ingredient. Democracy in substance rather than words is still pretty new even in Taiwan, after all.