THE signing into law of America's toughest bill on illegal immigration has led to immediate protests, reignited the divisive battle over immigration reform and angered the US President. Even before Arizona Governor Jan Brewer signed the bill - aimed at identifying, prosecuting and deporting illegal immigrants - President Barack Obama strongly criticised it. Speaking at a naturalisation ceremony for 24 active-duty service members in Washington's Rose Garden, he called for a federal overhaul of immigration laws, which congressional leaders signalled they were preparing to take up soon, to avoid ''irresponsibility by others''. He said the Arizona law, enacted on Friday...