Photo gallery: Obama delivers second inaugural speech

Four years ago, with the United States (US) economy on the edge of another Depression and his political future uncertain, President Barack Obama delivered a cautious inaugural address designed to lower expectations and avoid provoking his ideological foes.

He had no such inhibitions when delivering his second inaugural speech this week. With the economy on the mend and a tough re-election battle behind him, Mr Obama laid down clear ideological markers – from gay rights, climate change to income equality – that could influence Democratic politics and box in the Republicans for years to come.