NEARLY three days into their occupation of the debating chamber of the Legislative Yuan, Taiwan’s parliament, in Taipei, dozens of activists, mostly students, show no sign of flagging. They broke in on Tuesday evening, March 18th, and resisted attempts by the police to evict them overnight. Since then, a stand-off has persisted. The police are stopping new arrivals from joining them, but allow in food and water. The protesters include a team of white-coated medics. They look well settled. Three legislators from the main opposition, the Democratic Progressive Party (DPP), started 70-hour hunger-strikes just before the occupation. They are taking eight-hour shifts in the parliament to afford the protesters extra protection—to shift the students, the police will also have to manhandle the legislators. Outside, a crowd of several hundred ignores the drizzle to listen to speeches and songs, wave artificial sunflowers, and shout denunciations of the government and of Taiwan’s president, Ma Ying-jeou. The occupation was billed as lasting 120 hours, to block a plenary parliamentary session on Friday 21st March, and to provide a deadline for the government to meet the protesters’ demands. These are three-fold: they want Mr Ma to come to the chamber himself to apologise for the way in which his party pushed an agreement on opening up services trade with China through parliament on Monday (available here, in Chinese); they also want the parliamentary speaker, Wang Jin-pyng (who happens to be a rival to Mr Ma in the ruling party, the Kuomintang, or KMT ) to come to pay his respects; and they want legislation passed to institutionalise parliament’s right to scrutinise such agreements item by item.

The DPP insists the students are acting on their own initiative. But it is supporting their protest, which it believes is tapping a rich vein of discontent with the government, focusing on the services-trade agreement.

The sit-in was provoked by what the DPP sees as the KMT’s breaking of its promise to allow a parliamentary committee to review the agreement clause by clause. At a press conference on March 20th, the DPP’s chairman, Su Tseng-chang, portrayed this as a “key moment” for Taiwan’s quarter-century-old democracy, which he said the party would “do whatever it takes” to protect.

In less lofty terms, the DPP seems to have spotted an opportunity to exploit the unpopularity of a man they call “a 9% president”—a reference to the low point Mr Ma’s approval rating fell to last year in opinion polls—on an issue where they think he is weak. With local elections in December and a new presidential contest due in 2016, when Mr Ma will have to stand down, the DPP seems to think it has the KMT on the run.

Improving relations with China has been a central theme of Mr Ma’s presidency since he took office in 2008. In 2010 China and Taiwan signed the Economic Co-operation Framework Agreement (ECFA), significantly boosting cross-strait ties. The services agreement, signed last June, is part of the effort to implement that framework.

At the press conference, Mr Su spoke under a banner reading: “Demand substantial review; restart negotiations with China.” The DPP argues the agreement will hurt small businesses on Taiwan and is lopsided in some of its market-opening measures. But also, the party’s roots are in the movement that wants Taiwan to declare formal independence from China; it worries about Taiwan’s becoming too dependent economically on the mainland. Hsiao Bi-khim, one of the DPP hunger-strikers, thinks most people on Taiwan are behind it on this, since they have yet to see the benefits they were promised from ECFA. The economy is still, by local standards, sluggish.

For his part, Mr Ma may be thinking about his legacy, and wanting to use his remaining years in power to make a breakthrough in relations with China. Last month Nanjing in China played host to the first formal meeting between ministers from China and Taiwan in their government capacities since the end of the civil war in 1949 formalised the division. A next step would be a summit between Mr Ma and China’s president, Xi Jinping. Hopes that the Asia-Pacific Economic Co-operation summit in Beijing this autumn might provide an opportunity are fading. But it would be easier to achieve a meeting elsewhere if the implementation of ECFA were going well.

In the shorter term, however, Mr Ma has a nasty local problem. The students say they will not leave after their five-day deadline if their demands have not been met; and they may take their “occupy” strategy to other targets: Mr Ma’s own office, for example.

It is already highly unusual for a government to have tolerated the seizure of parliament by protesters for so long. But, fearful of the ugly headlines using force against peaceful students would attract, it does not have many easy options.