Immigration and connecting flights

I have been reading a lot about how long it can take to clear immigration on entry to the US. We have a connecting flight to Vegas - if we miss the flight because of delays in immigration what do we do? Will our airline (Continental) put us on the next flight? The connection time is 2 h 55.

Thanks

Immigration and connecting flights

Unless your plane from the UK is very delayed, you should have no problem with a 3 hour layover. If you miss the plane they will try to put you on the next one if there are seats available