Nationalism is in crisis as more Catholics define themselves as Northern Irish, Peter Robinson claimed.
A section of Catholics hold views on social issues, education and the economy which are not reflected in the positions of the SDLP and Sinn Fein, the DUP leader added.
"There is new political space developing in Northern Ireland," he said.
"It is the DUP's aim that unionism will own it and lead it. The people in this space do not fit the stereotypes.
"They are not coming with a textbook nationalist wish-list demanding it be satisfied but rather they want to know what we will deliver for them, their family and Northern Ireland."
Mr Robinson, addressing a South Antrim party dinner on Saturday night, said the fastest growing section of society is that which classifies itself as "other". The fastest growing identity group is that whose members classify themselves as Northern Irish.
"While the reaction of commentators may have erred on the unthinking, the reaction of nationalism has opted for the hysterical," he said. "This reaction is not a surprise to me as it reveals where the real political crisis lies - in Irish nationalism."
He claimed the republican goal of a united Ireland was as far away as ever.
"Their grand plan by their grand strategist (Gerry) Adams has failed. To avoid the hard truths of home he wanders the world trying to convince the ignorant and the gullible that it'll happen any day now," he said.
Mr Robinson has previously called for change in the practice of schooling Catholic and Protestant children separately, a proposal criticised by the Catholic Church.