The possibility of an incursion by the Turkish military depends to some extent on the internal politics of Turkey. From this perspective, if you see incursion as a negative, there are several encouraging signs .
Firstly, there is the victory of the governing party, the AK party, in Kurdish regions against candidates of the Kurdish DTP party. In fact the early indications are that the ruling party won the majority (about 52%) of the Kurdish votes. Of course the candidates from AK are also of Kurdish origin, but then there have always been Kurdish politicians in all parties - and if you include those of mixed Kurdish-Turkish heritage they probably make up a significant proportion of the politicians. As opposed to these "mainstream" parties which are defined by their generic ideological and policy positions the DTP is identified as a Kurdish party mainly concerned with Kurdish cultural and political rights. In the 2002 elections the DTP failed to get into parliament because of a 10% threshold requirement for parties to get into parliament. Some argued at that time that their loss (they got about 5% of the vote) showed that the "Kurdish issue" was really more of a Southeastern issue - one of poverty and underdevelopment in the Southeast - than an ethnic issue. However, many felt that because of distortions due to the threshold no valid conclusions could be drawn. To get around the threshold requirement this time around the DTP members contested the election as independents. They won 23 seats but they lost in many places to AK. This has had two effects. One was the demonstration of an acceptance by the Kurdish electorate of the southeast that the AK, a national "mainstream" party, could represent their interests. The other was the recognition by the DTP that narrow "ethnic" issues would no longer be sufficient to guarantee them support in the southeast. This is evident from their post election statements in which the newly elected DTP parliamentarians promise to pursue a more accommodating approach and focus on issues of economics and development for the region rather than on cultural issues. This is a far cry from the last time a Kurdish party was in parliament when symbolic actions took precedence. The DTP is not giving up cultural issues just changing their focus. In the long term both of these outcomes bode well for the stability of the region. If we have the luxury of thinking in the long term.
In terms of the short term both these factors have considerably strengthened the non-interventionist forces within the AK. The increased strength of the AK in the southeast also means an increased sensitivity to the southeast where intervention would not be welcomed. Furthermore, a "reasonable" DTP would be able to provide support to the AK in these matters. Finally, the impressive showing by the AK in the elections, even if they did not increase their number of seats in parliament, gives them a much more powerful voice than they had before. Given this, barring a preemptive move by the interventionist forces within the military and their political supporters, the AK has a breathing space. Reports were that Condi has promised action on the PKK to the Turkish government if they would just give her some time. There is time now for those actions. Under different circumstances I would be feeling very optimistic right now. But after seeing the incompetence of the last six years I fear that we will let this opportunity pass. I hope I am wrong.
Update:
Turkish newspapers are playing up the column in the July 30th issue of the Washington Post by Robert Novak. He had this to report about the US response to Turkish requests for action against the PKK
The surprising answer was given in secret briefings on Capitol Hill last week by Eric S. Edelman, a former aide to Vice President Cheney who is now undersecretary of defense for policy. Edelman, a Foreign Service officer who once was U.S. ambassador to Turkey, revealed to lawmakers plans for a covert operation of U.S. Special Forces to help the Turks neutralize the PKK. They would behead the guerrilla organization by helping Turkey get rid of PKK leaders that they have targeted for years.Given the neocon credentials of Edelman and the standard neocon approach to problems (what would Jack Bauer do?), the report seems credible. Whether, this approach can be successful depends on if there is substantial buy-in from the Kurdistan Regional Government (also known as the Talabani and Barzani clans). Even then I would rate the chances of operational success low. However, on a PR front, even a failed attempt can only help the perception of the US in Turkey.