Rotte, like other Asia experts here, has followed the immolations with sad fascination.
Buddhism's first injunction is against harm - to others or self, she said. At the same time, stories that honor the principled sacrifice of one's life abound in the Dharma.
In one famous tale, the Buddha and a disciple were walking through a forest when they came upon a tigress that had given birth to five cubs. Exhausted, unable to hunt, the beast's only chance for survival was to eat her cubs.
The Buddha sent his follower to find meat from a lion kill while he stayed with the tiger. But the disciple was slow to return. In the meantime, out of immense compassion for the tigress' suffering, the Buddha offered her his own body so she could survive and nurse her cubs.
"That's the way in which it's best for me to understand what the monks have done," Rotte said.
Chinese government officials have condemned the immolations and accused the Dalai Lama, Tibet's exiled spiritual leader, of encouraging and inciting them.
Immolation is a horrible way to die, which is what gives the act its power.
What to Americans may be the most famous sacrifice occurred during the Vietnam War, when Buddhist monk Quang Duc lit himself ablaze on a Saigon street in 1963 in protest against the government.
The practice soon reached the United States.
In March 1965, 82-year-old peace activist Alice Herz immolated herself in Detroit, having told friends she decided to follow the Vietnamese monks. Eight months later, Pennsylvania-born Quaker Norman Morrison set himself ablaze outside the Pentagon, below the office of Defense Secretary Robert McNamara. A week after that, Roger Allen LaPorte set himself on fire in front of the United Nations building in New York.
Others from Czechoslovakia to India employed the same, terrible tactic in succeeding years. In December, the self-immolation of an unemployed college graduate helped trigger a crisis in Tunisia that forced out the president and sparked more than a dozen similar suicides across the Middle East.
Among Tibetans, most of the immolations have occurred in the small town of Aba, in Sichuan Province, China, which has a significant Tibetan population. In Philadelphia and other cities, Tibetan groups have held candlelight vigils to remember the dead.
"Our community is in crisis and we need the help of every government to call on China to stop the oppression," said Karma Gelek, president of the Tibetan Association of Philadelphia. "We are fortunate to live in the United States, where we can protest peacefully and 'occupy' cities. In China, we would be arrested and jailed."
Local Tibetans will go to Washington on Wednesday to join a global protest and will take part in a one-day global hunger strike on Saturday.
The immolations started after Chinese authorities ordered greater curbs on religious freedoms.
"It tends to be shocking for Westerners, but there's a long history of this kind of action, especially in Chinese Buddhism," said David Carpenter, director of the Asian studies program at St. Joseph's University. "It's not really accurate to view it as suicide. It's giving up one's life in an act of generosity. . . . What they call 'abandoning the body' is a high form of devotion."
It's unclear whether monks in their 20s and 30s, raised in a country where the media are tightly controlled, know that history, he said. On the other hand, "these young monks may see themselves as walking in the footsteps of the Buddha."
Why so many? Why now?
Rotte noted that the Dalai Lama recently resigned as political leader of the Tibetan people, retaining only his religious role. That has caused uncertainty. At the same time, Chinese authorities are telling monks in Tibet how to practice and turning their temples into tourist sites.
"I wouldn't use the word desperation or despair - definitely it shows that there's tremendous anguish, and it's reaching very far into one's heart and mind to say, 'I will make this offering,' " Rotte said. "I think the communication is more to the world community than directly to China. One would hope China would pay attention."
Contact staff writer Jeff Gammage at 215-854-2415, email@example.com, or @JeffGammage on Twitter.