text:  While ironclads spread rapidly in navies worldwide , there were few pitched naval battles involving ironclads . Most European nations settled differences on land , and the Royal Navy struggled to maintain a deterrent parity with at least France , while providing suitable protection to Britain 's commerce and colonial outposts worldwide . <unk> remained , for the British Royal Navy , a matter of defending the British Isles first and projecting power abroad second . Those naval engagements of the latter half of the 19th @-@ century which involved ironclads normally involved colonial actions or clashes between second @-@ rate naval powers . But these encounters were often enough to convince British policy @-@ makers of the increasing <unk> of strictly naval foreign intervention , from Hampton Roads in the American Civil War to the <unk> combined defences of naval <unk> such as <unk> and Cherbourg . 
  