There is a pervasive sense of unreality. This kind of tragedy - a mass shooting and home-made explosive devices - happens elsewhere, not here.
There is disbelief that this has happened at all, at the dozens of dead people, and shock that a Norwegian could do this to other Norwegians. There is grief too that so many young lives have been lost in such a senseless way.
"I feared I would have nightmares overnight, but the nightmare came when I woke. This is impossible!" lamented Per Martin Hvam-Malmedal, a student.
Norway has a small population, so a relatively large proportion of people will be directly or indirectly touched by the events. In the streets and online, people are rallying to support each other.
This is a society where you can meet even top politicians strolling in Oslo's streets with no security.
The attack was squarely aimed at the values Norwegians treasure most. Their openness, freedom of expression and feeling of safety have all been shaken to the core.
On Utoeya Island politically active youngsters gather every summer to play football, participate in debates and meet the Labour Party leadership, former and present. In the words of Prime Minister Jens Stoltenberg, what was once a paradise for young people has been turned into hell.
Norway's dark corners:
Norway's openness and lack of security is in large part a result of it having such a small, homogenous population. It seems paradoxical that an extremist who appears to have fanatically wanted to protect Norway from intruders and the "dangers" of multiculturalism would himself do such damage to the nation.
Norway is now forced to look at the less attractive facets of its society.
Media reports say the arrested man expressed sympathies for the Progress Party (FrP), Norway's most right-wing mainstream political party. For many years, the FrP has been steadily growing in popularity at the expense of the left-leaning Labour Party and the more moderate Conservative Party, although it is yet to win an election.
There are also citizens' websites like Document.no, where Anders Behring Breivik left racist, extremist right-wing comments along with fellow anti-Muslims, and there were attempts to start up Norwegian satellite groups in support of the English Defence League.
These all represent, with varying degrees of extremism, a section of the Norwegian population which feels that the country's immigration policies are too lax. They feel disenfranchised despite Norway's attempts at distributing fairly its immense oil wealth. Norway might now be forced to deal head-on with this undercurrent of nationalism and anti-immigration sentiments.
Justice Minister Knut Storberget said the attack "is sure to change Norway... I hope we will come to value more highly the democratic and open work done by youth and others in political and voluntary organisations".
There is some relief that however tragic, the attacks were apparently not the work of international terrorists.
That at least gives less ammunition to those who are trying to stoke up anti-Muslim feelings.
But Norwegians fear their cherished freedoms may be affected in the aftermath.
"We should not let fear paralyse our ability to think clearly and wisely," wrote Harald Stanghelle, political editor of the daily Aftenbladet. "There is much that we should not allow to be sacrificed on the altar of fear."
Lars Helle, editor of the daily Dagbladet, said "we must avoid being preoccupied by fear, like the US was after 11 September 2001. Rather, we must look to Spain and England and how the people of those nations recovered their freedom after the horrible terrorist acts of 2004 and 2005".