@bunny please do not cancel your trip to Europe. I am Irish, I live in Dublin and I have lived in Germany and London. London, Germany and Ireland are just as safe as where you live, just as safe as going to
Disneyland California, just as safe as going to New York, Chicago, Boston, or anywhere else.
Despite what people think, individual American tourists walking down the street are not specifically targeted. You could get run over crossing the street in London but then again the same thing could happen in your home town.
Gun laws in Europe are far far stricter than in America, so for example you wont get caught in a drive by shooting, people don't carry loaded guns on a day to day basis, you wont see guns being sold in supermarkets.
In Ireland you are even more safer, as we are a military neutral country and we are not an official member of NATO. We do not send troops to fight in wars ie Iraq or Afghanistan. Instead our armed forces work as peacekeeping troops with the UN.