Have you looked more into Yemeni child marriages? There are Christians, Jews etc..., not just Muslims. They aren't outlawing just because of Islam, it is tribal actions.
A person can marry a physically and mentally matured girl. However, if she don't like it, they shouldn't force her to marry. Even if Islam allows to marry a physically and mentally matured girl, Islam tells to find a good bride which suits her better and not to force it.
The countries you tell makes their rules. They have made many rules wich Islam hasn't told, for example, imprisoning a man who drink alcoholic drinks without license or in public.
See this:
CHILD BRIDES: A GLOBAL ISSUE
CHILD BRIDES: A GLOBAL ISSUE
Jewish girl wears golden ceremonial dress and gold and silver jewelry necklaces traditionally worn by Jewish brides in Yemen.
Despite numerous campaigns from many of the world's largest charities and NGOs, the issue of child brides remains a global concern.
There are currently some 57.5 million child brides across the world, 40 per cent of which married in India.
Forty-six per cent of women in India were married before the age of 18, according to the National Family Health Survey-3.
Meanwhile, in Africa, 42 per cent of girls were married before turning 18 compared to 29 per cent in Latin America and the Caribbean.
But the number of child brides is estimated to rise to 140 million by 2020 if current trends continue, 18.5 million of which will be under 15 years old, analysts warn.
Statistics show that girls living in poor households are almost twice as likely to marry before 18 than girls in higher income households.
'It was not fair at all and the marriage should not have happened even if some tribes believe that it is a good custom.'
The practice of marrying young girls is widespread in Yemen and has attracted the attention of international rights groups seeking to pressure the government to outlaw child marriages.
Yemen's gripping poverty plays a role in hindering efforts to stamp out the practice, as poor families find themselves unable to say no to 'bride-prices' that can be hundreds of dollars for their daughters.
Tribal custom also plays a role, including the belief that a young bride can be shaped into an obedient wife, bear more children and be kept away from temptation.
Destaye’s wedding wasn’t what she had always dreamed of. She wasn’t celebrating her union with the man she loved.
She was 11 years old, being forced to marry Addisu, a 23-year-old Ethiopian Orthodox priest who had chosen her to be his wife because she was young enough to ensure that she would still be a virgin. That day, she felt ashamed.
Worldwide, by 2010, about 67 million women 20 to 24 years old had been married before they were 18, according to the Population Fund. Child marriage is found in all regions of the world but is most common in South Asia and sub-Saharan Africa, both proportionally and in count. Most countries, including Ethiopia, have laws preventing it, but most of them do not enforce those laws.
. See something about anarchism .... 
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