Aliens arriving by boat may be political refugees in desperate straits and fleeing from war or persecution; or they may be the human cargo of sophisticated smuggling operations, people who have paid large sums of money, pushed by the lack of opportunity at home and pulled by unrealistic expectations. Arriving in unscheduled , and often repurposed old fishing, boats means they avoid the conventional immigration procedures. Their favoured destinations are countries with liberal asylum laws.
The Central Mediterranean Route, which runs primarily from Libya to Italy, has been called the world’s most dangerous migration route . The International Organization for Migration (IOM) reported that since 2014, more than 17,000 people have died or gone missing en route. In the first three months of 2022 alone, up to 600 people attempting to reach Europe had gone missing. In 2017 Italy and Libya signed an agreement that placed the responsibility to intercept and return smugglers and asylum seekers on the Libyan Coast Guard (which reportedly has deep connections to the militias that rule the country); UNHCR data shows that the likelihood of dying in Lybya's the near-shore waters had since more than doubled. There have additionally been reports of the horrific treatment faced by asylum seekers after they have been intercepted and then returned to Libya. Many of those returned are unaccounted for.
About 100,000 illegal Chinese aliens arrived to the USA by the boatload for several years between 1987 and 1991. Chinese applicants for refugee status quadrupled; in 1993, the backlog of asylum cases was more than 300,000, often left pending for years while applicant were allowed to work legally.
Over the period 1975 to 1992, more than 1.6 million Vietnamese fled their homeland. No one knows how many were drowned at sea or slaughtered by pirates. The mass exodus slowed to a trickle in 1992, with only 12 arriving in Hong Kong, 18 in Indonesia, nine in Thailand, one in Malaysia, and none at all in Singapore, Macau or the Philippines. In 1989, the number of arrivals reported by Southeast Asian countries was 70,000, in 1990 it was 32,000, and in 1991 it was 21,900. A 1992 study estimates 850,000 boat people settled in the USA as a result of the Vietnamese diaspora alone.