When President Obama wept at a recent press conference to announce action on gun control, his tears might have been born of frustration as well as sadness. Despite frequent mass-shootings, events which some might think would strengthen the case for tighter gun laws, it is difficult for any politician or party to change the rules on gun ownership in the US. One organisation is often credited with, or blamed for that - the National Rifle Association, or NRA. This programme is not about the arguments over gun control but about the NRA itself. Few could dispute its success. Even if one allows for the possibility that it reflects the public mood, rather than shapes it, it has unquestionably changed the gun debate in Washington DC. So how has it done it? Former NRA insiders recall how the NRA was transformed from a hunting and marksmanship club into a political lobbying group in the 1970s, and the tactics it used from then on to influence Washington lawmakers by organising its huge grass roots base. (Photo: US-Politics-Guns-NRA, Credit: Karen Bleier/Getty Images)