What was the most serious incident of religious terrorism on U.S. soil prior to September 11, 2001?

The most serious incident of religious terrorism on U.S. soil prior to September 11, 2001, was the vehicular bomb attack at the World Trade Center in 1993. This incident was orchestrated by individuals motivated by a radical interpretation of Islam, intending to cause mass casualties and instigate fear. The perpetrators believed that by causing significant destruction at a symbolic location, they could advance their ideological goals and provoke a larger conflict.

The choice of the World Trade Center as a target was particularly significant due to its global economic symbolism, which the attackers sought to undermine. The bombing resulted in the deaths of six people and injuries to over a thousand, marking it as a pivotal moment in the history of domestic terrorism linked to religious extremism.

While the other incidents listed were indeed serious and tragic, they do not specifically align with the context of religious terrorism in the same way, which is why the 1993 World Trade Center bombing stands out in this regard. This foundational event highlighted vulnerabilities in U.S. security and foreshadowed the larger scale of attacks that would occur in the future, including those on September 11, 2001.