Church burnings, religious slurs and demonstrations over who has the right to the word Allah are tell-tale signs of Muslim extremism. They are not what we expect of Malaysia, a nation with a tradition of Islamic moderation, and ethnic and religious tolerance. Yet such incidents are increasingly frequent, spurred by leaders using Islamist nationalism to woo voters. If decades of stability and growth are to continue, the authorities need to curb these excesses and ensure a return to unity. Prime Minister Najib Razak is trying to stimulate the economy by luring foreign investors, and the slogan 'One Malaysia' is being used to attract tourists. Neither campaign is working as it should; the violence has sparked worries at home and abroad. Investment and tourism require a stable political and social environment. The pigs' heads placed outside mosques in Kuala Lumpur yesterday and the attacks on churches, a Catholic school, a Sikh temple and Muslim places of prayer point to spreading unrest. The attacks began after a court on December 31 overturned a government ban on the use of the word Allah by Christians. Like Arab Christians and Jews, Malaysia's Malay-speaking indigenous Christian communities use the term when referring to God. But only in Malaysia has the matter become one of religious ownership. The National Front coalition government, headed by a Malay nationalist party, is using it to bolster declining Malay Muslim support. Such policies have worked in the past, but in an era of Muslim radicalism they can be dangerous. Landslide election losses in 2008 in favour of opposition parties headed by former deputy prime minister Anwar Ibrahim were telling; his campaigning was based on uniting the majority Malay and Chinese, Indian and ethnic communities. Malaysians are, after all, interested less in Muslim nationalism than an end to the recession, improving their lot financially and ridding the nation of corruption. Using the religion card will stir discontent and open divisions rather than win widespread support. Malaysia's secular character has to be maintained. Otherwise, radical Islam could harm the nation and its relations with neighbouring countries. Government challenges to the court's ruling have to be dropped. Now, Najib and other top-level officials must direct their efforts to unifying the country and not allowing it to be torn apart.