higher yield

Fission

• Trinity
• Hiroshima
• Nagasaki
• Crossroads Baker (first underwater)
• Ivy Mike (first fusion bomb, 90% fission yield)
• Ivy King (highest yield fission bomb)
• Castle Bravo (first dry fuel fusion bomb, 90% fission yield)
• Castle Romeo (test of first deliverable fusion bomb, MK-17)
• Redwing Zuni (test of first clean fusion bomb)
• Redwing Navaho (test of clean fusion bomb, only 5% fission yield)
• Tzar Bomba (highest yield fusion bomb, USSR)
• etc.

"Dial-a-yield," or Variable Yield, is a method of adjusting the yield of a nuclear weapon through various means. While most modern high-energy weapons are thermonuclear, both fission and thermonuclear weapons can have their yield adjusted. In a boosted fission weapon (which can also be the primary to a staged radiation implosion weapon), the yield can be adjusted by changing the amount of deuterium/tritium gas that is injected into the plutonium pit, or by the timing of the external neutron initiator, or both. In a staged weapon, causing the secondary to not ignite by adjusting the yield of the primary (see above), or blocking the radiation channel in some way, can also change the yield of the weapon.

People were/are worried about fusion bombs for the same reasons they were/are worried about fission bombs, except more so because the yield of a fusion bomb is typically much higher than the yield of a fission bomb. So a fusion bomb typically does more of everything a fission bomb does.