Shortly after opening the museum became the centre of controversy over its interpretation of the Combined Bomber Offensive during World War II, in which some 20,000 Canadians participated in. Much of the controversy stemmed from two assertions made by on a museum label, that the bombing offensive was largely ineffective until later in the war, and that its morality and value of strategic bombings remained contested. Complaints from Canadian veterans prompted another Senate Subcommittee to be launched. Museum staff eventually removed the offending museum label, replacing it with another label with text three times in length that "glossed over the salient facts;" although the offending images remained.