Declaring an end to “mindless austerity,” President Barack Obama called for a surge in government spending Thursday, and asked Congress to throw out the sweeping budget cuts both parties agreed to four years ago when deficits were spiraling out of control. Obama’s proposed $74 billion in added spending—about 7 percent—would be split about evenly between defense programs and the domestic side of the budget. Although he’s sought before to reverse the “sequester” spending cuts, Obama’s pitch in this year’s budget comes with the added oomph of an improving economy and big recent declines in federal deficits. Taking a defiant tone,...