bandwagons
You can refer to an activity or movement that has suddenly become fashionable or popular as a bandwagon.
the environmental bandwagon.
环保潮流。
If someone, especially a politician, jumps or climbs on the bandwagon, they become involved in an activity or movement because it is fashionable or likely to succeed and not because they are really interested in it.
In recent months many conservative politicians have jumped on the anti-immigrant bandwagon.
最近几个月,许多保守党政客赶上了反移民的浪头。