That is the wrong question, in my opinion. It can also be a deceptive rhetorical trick. The validity of a critique is not dependent upon the critic having a suggestion for an alternative.
"We'd all love to knock them upside the head, but..." I do have a suggestion, after all. I suggest that we abandon taking that line of reasoning seriously. Were it true that "we'd all love to..." it would have long since happened. It is the "but" that is doing all of the heavy lifting in that sentence, and over the years we have seen that there is an endless list of "reasons" that can follow that "but."
Thank God the Abolitionists and enslaved people didn't listen to those Whigs in the 1850s who said "we'd all love to end slavery, but legally..." They were up against much longer odds. The Women's Suffrage movement leaders, the early organized Labor leaders, the Civil Rights leaders - they all rejected that line of thinking as well.
It is the necessary will, the courage and the integrity that are missing, not the right method.
Fredrick Douglass:
Let me give you a word of the philosophy of reforms. The whole history of the progress of human liberty shows that all concessions yet made to her august claims have been born of earnest struggle. . .
If there is no struggle, there is no progress. Those who profess to favor freedom and yet deprecate agitation are men who want crops without plowing the ground. They want rain without thunder and lightning. They want the ocean without the roar of its mighty waters.
The struggle may be a moral one or it may be a physical one, or it may both moral and physical, but it must be a struggle. Power concedes nothing without a demand. It never has and it never will. Find out just what a people will submit to, and you have found out the exact amount of injustice and wrong which will be imposed upon them; and these will continue till they are resisted with either words or blows, or with both. The limits of tyrants are prescribed by the endurance of those whom they oppress.
Rev. Dr. Martin Luther King Jr. in the Letter from Birmingham Jail:
Shallow understanding from people of good will is more frustrating than absolute misunderstanding from people of ill will.