Paris — Representatives of 30 nations meeting in Brussels vowed to beef up nuclear energy Thursday as one solution to meet climate-fighting targets and guarantee reliable energy supplies. But the issue of nuclear power is divisive, and critics say it shouldn’t be part of the world’s approach to energy challenges. The summit was the first of its kind, drawing leaders and delegates from the United States, Brazil, China and France, among others. The International Atomic Energy Agency, or IAEA, co-hosted the meeting and is promoting nuclear energy as a key way to reduce skyrocketing climate emissions. IAEA chief Rafael Grossi said, “The heads of government, presidents, they believe that in the current context energywise, securitywise, nuclear has a very important contribution to make.” Over 400 nuclear plants operate in about 30…