Everyone in Poland is mourning the catastrophic plane crash in a forest near Smolensk that killed the nation's president, his wife and 94 other senior members of the Polish political elite. The officials were on their way to a ceremony commemorating the 70th anniversary of the execution of as many as 22,000 Polish officers and intellectuals by the Soviet secret police
But beyond their grief, the Polish people are asking an unavoidable question: What caused the crash?
The plane itself, as has been noted, was far from modern. A Russian-made Tupolev, it had flown in the service of the Polish government since 1972, but officials have said it was carefully serviced and in good condition.
The safety of the airport, which is opened only for special occasions, has been questioned. But Polish Prime Minister Donald Tusk flew there without problems only three days earlier to meet Russian Prime Minister Vladimir Putin at the Katyn graves of the Polish and Russian victims of Soviet terror.
Attention has also focused on the dense fog covering the ground around Smolensk in the early hours of the fatal day. The airport was not equipped with technology to allow planes to land safely in fog.
All of these factors are likely to have contributed to the catastrophe, but none alone is likely to have caused it.
It may well be that an underlying and more human contribution to this tragic drama was President Lech Kaczynski's feeling that he had been left out of the ceremonies that had taken place in Katyn three days earlier between the Polish and Russian prime ministers. According to news reports, Kaczynski had trouble reconciling himself to the fact that Tusk, his political archrival, had stolen the show in commemorating the mass murder at Katyn, and he was eager to reclaim some of the limelight.
During the Soviet era, the executions in Katyn Forest were officially blamed on the Nazis. For generations, Poles had to live with the knowledge of this historic atrocity, at the same time enduring official denial of responsibility by the real perpetrators. This year's ceremonies were intended to both commemorate the deaths and begin the healing. Now, instead of final resolution, the anniversary has brought Poland an almost unthinkable tragedy.
The trip was not an official presidential visit, and it took place after months of Kaczynski's insistence on making the journey. He was determined also to take a substantial and respectable entourage with him to Smolensk: members of parliament, the highest-ranking military commanders, ministers, administrators and personal staff.
If past actions are any indication, the president would have been extremely reluctant to abort his trip once he had started. Earlier in his term, on Aug. 12, 2008, he flew to Georgia to express his support for its isolated president, Mikheil Saakashvili. On that occasion, he demanded that the pilot land in the Georgian capital, Tbilisi, despite the threat of ground fire from Russian forces. The pilot refused to endanger the plane and the president himself, and landed instead in Azerbaijan. This angered Kaczynski, and a row ensued on board. Yet the pilot did not yield.
Could it be that on Saturday there was pressure on the pilot to disregard advice from ground services not to land in foggy Smolensk and instead land in Moscow or Minsk? Diversion would have been a reasonable decision, except that either alternative would have made the president and his entourage late for the ceremonies at the mass graves.
Polish pilots of the famous British Royal Air Force Division 303 distinguished themselves in combating the Nazi air raids during the Battle of Britain in World War II. Since then, Poles have taken pride in the skill and bravery of their pilots.
But that reputation comes with considerable pressure, and there have also been tragedies. A little more than two years ago, for example, a reliable Spanish-made military plane, a CASA C-295M, crashed while approaching the airfield in Miroslawiec in northwestern Poland.
The attempted landing, like the one at Smolensk, occurred in bad weather conditions with little visibility. All 20 people on board died: four crew and 16 high-ranking officers of the Polish air force. They were returning from a conference devoted to air traffic safety.
We hope the black boxes will tell the whole story of Saturday's crash. But it will be no surprise if the pilot felt unable to resist pressure from the president and the top brass of the Polish military.
Adam Chmielewski is a professor of philosophy at the University of Wroclaw in Poland and the author of "The Psychopathology of the Political Life." Denis Dutton is a professor of philosophy at the University of Canterbury in New Zealand and editor of the website Arts & Letters Daily.