The phrase "appalling attack" refers to a harmful and shocking act of aggression or violence that is considered very disgraceful and unacceptable. Full definition
«Planned Parenthood League of Massachusetts stands with people of color, Jewish people and allies in the face of such appalling attacks fueled by hate.» (plannedparenthood.org)
Mervyn Thomas, Chief Executive of Christian Solidarity Worldwide (CSW), said: «We extend our heartfelt condolences to those who have lost loved ones in these appalling attacks. (premierchristianity.com)
On September 12th, the North Atlantic Council met again in response to the appalling attacks perpetrated yesterday against the United States. (politics.stackexchange.com)