Recently we have seen mosques used to preach hatred; to spread exhortations to terrorist activity; to house a bomb factory; to store weapons; to disseminate messages from bin Laden; to demand (in the U.S.) that non-Muslims conform to Islamic dietary restrictions; to fire on American troops; to fire upon Indian troops; to train jihadists; and much more.
In light of all that, it is entirely reasonable for free people to oppose the construction of new mosques in non-Muslim countries.
“EDL Stage Rooftop Protest at Mosque Site in Dudley,” from the EDL site, May 2 (thanks to Pamela Geller):
Some of our supporters are at present barricaded on the roof of a derelict building near the site of the proposed £18m Mega Mosque in Dudley. They have food and water to last them weeks, and a pa system to give speeches. I believe they even have a Playstation! They will be playing the call to prayer to let those who are not bothered by this Mosque know what to look forward to.
Pamela has more details here, and is updating on the situation periodically.