The phrase "a common thread unites" is correct and usable in written English.
It can be used to indicate that there is a shared element or theme that connects different ideas, people, or situations.
Example: "In our discussions about various cultures, a common thread unites their values of family and community."
Alternatives: "a shared connection binds" or "a unifying theme links".
Notwithstanding their differences, however, a common thread unites them: China is presented as the dominant agent.
A common thread unites the most abstract philosophical speculations and childish beliefs in ghosts; a deep respect for nonviolence and the bloodiness of certain sacrificial rites; extreme asceticism and the sexual aspects of Tantric worship.
While of varying cultures, a common thread unites them all -- a strong commitment to supporting their daughters' education.
A common thread uniting nearly all of Mr. Cooper's performances is that his characters have been defined by ample smoothness and sex appeal.
If challenged to come up with a common thread uniting its featured acts, the best I could come up with is that if they were touring in Florida, they'd all probably pop into Miami Ink to get a tattoo done.
In addition to raising awareness about breastfeeding, the Lansinoh campaign highlights how nursing is a common thread uniting families from all different backgrounds.
Here, one common thread unites Republicans, Democrats, blacks and whites, men and women, young and old: People just don't believe the news.
Prioritisation is a common thread that unites so many successful list strategies, such as the "1-3-5" approach, (toy to achieve one big thing, three medium things, and five small things per day) or the similar "3+2" strategy.
This is the common thread uniting the opponent of gay rights, the anti-government zealot and the white man who cannot accept the idea of a black president.
But there was one common thread uniting most of the women in the study: Their illness was generally overlooked by doctors.
