The idea that standing up to terrorism by way of air strikes in Syria has made the UK less safe is "simply wrong", the Defence Secretary has said.
Michael Fallon said the vote in Parliament last week to extend RAF air strikes into that part of Islamic State (IS) territory was an "important moment" in the international campaign against the extremists.
Speaking during a visit to the Pentagon he hailed Britain's relationship with the US, pledging to build on the strong partnership.
He said: "The United States remains our closest strategic partner and we will work together to promote global stability, to protect our shared interests and to deliver prosperity for our people."
During the joint press conference with US secretary of defence Ash Carter, Mr Fallon addressed concerns that bombing Syria would increase the threat from IS, also know as Isil or Daesh, to the UK.
He said: "There will be plots against both our countries as we take the fight to Isil-Daesh, just as there have been attacks like those in San Bernardino. But we must not allow the idea to take hold that standing up to this terrorism makes our homeland security any worse.
"That is a council of despair and simply wrong. So we must defend our values as much as our streets and always remember that these people don't hate us because of what we do, but because of who we are."
Mr Fallon said the UK had, since last week's vote, more than doubled the number of missions flown by the RAF to target IS "in its heartland".
He reiterated that Britain would not be sending ground troops into Syria or back into Iraq, explaining that "home-grown forces" - which could enjoy the support of locals - would be needed to provide security in areas liberated from IS.