Why did hard line communist leaders resent Mikhail Gorbachev?

Gorbachev's call for major political reforms as well as economic ... As if to counter hard-line statements in the region, a senior Hungarian Communist official issued a ... "I do not think the turn in the Soviet Union was too sharp," he added

The Communist party took control over the soviet union to try and stop Gorbachevs "perestroika" program.