CHIANG MAI - The timing of Myanmar opposition leader Aung San Suu Kyi's return to Europe after a 24-year absence could have been better. She leaves her country amid turmoil in its western Rakhine State, where sectarian rioting has claimed scores of victims. The period of unrest has shed a rare light on the volatile tensions that have simmered for years between the country's dominant Buddhist population and its Muslim minority.

The week of rioting has also put Myanmar's much lauded democratic transition under new international scrutiny. A realization seems to be emerging of the many shortcomings of President Thein Sein's reform program that, for all its surface glint, has failed to address the deep underlying grievances among the country's many ethnic groups.

At the same time, the situation presents the most challenging test in years of Suu Kyi's ability to heal rifts and lead her people. Her decision to press ahead with the trip to Europe, where she will belatedly receive her 1991 Nobel Peace Prize, could represent a political misstep given that the unrest marks the most clear-cut threat yet to the fragile reforms that, ironically, allowed for her election to parliament and afforded her the freedom to travel.

The violence has also spotlighted a far-reaching xenophobia within Myanmar's pro-democracy movement, long viewed by the outside world as drivers of positive change and equality. In now infamous comments, Ko Ko Gyi, a former political prisoner who led the 1988 student uprising that was crushed by military force, referred to Myanmar's long-persecuted Muslim minority group, the Rohingya, as "terrorists" who are "infringing on our sovereignty."