After two decades of fairly widespread progress toward consolidated democracy, the last several years have brought some notable setbacks, linked to the election of conservative nationalist parties.
First, it was Hungary. A Christian nationalist party called Fidesz won a free and fair election in 2011, which granted it a supermajority in the country's unicameral parliament. The party then used its power to rewrite the country's constitution to permanently hardwire Hungary's political system in its favor. The reforms crippled the independent media and judiciary. They also changed the electoral system and redrew districts to make it extremely difficult for opposition parties to win a majority. Finally, they required 2/3s majorities for any future government to agree on replacing electoral commissioners, judges and other important officials. Read this post by Kim Lane Scheppele for a concise and depressing summary.
Essentially, the massive electoral victory allowed Fidesz to engage in a wholesale restructuring of the Hungarian state; the party then forced through a constitutional overhaul that locks those policies in place no matter what future governing majorities might think.
Now Poland is exhibiting several alarming similarities to Hungary.
The newly-elected government of the Law and Justice Party (PiS) has pushed through reforms that limit the power of the Constitutional Court to review government policy for constitutionality and stack the court with PiS appointees. A law cracking down on the independence of public media and making it more nationalist in scope appears to be next. We'll see where this goes, but the trajectory is not good.
Both Fidesz and PiS are conservative, nationalist, Christian-identified parties.
While both of these developments are alarming and discouraging, they do raise fundamental points in democratic theory: What issues should merely be "policy" issues that can be changed by regular order, and which ones rise to the level of needing enshrined in a national constitution and requiring supermajorities to change?