Thomas Crooks, who attempted to assassinate Donald Trump, had researched and saved images of Kate Middleton on his phone before the attack, along with searches for other public figures like Trump and Biden. The FBI revealed that Crooks had scoped out the rally venue beforehand, leading to questions about security measures. The incident is being investigated as an act of domestic terrorism, with pressure mounting on the Secret Service for lapses in security. Despite Crooks' fixation on Princess Kate, there is no evidence of plans to travel to the UK, and the royals have not commented on the matter.