After picking on Bradley, it seems appropriate to respond with an alternate proposal. Most of what Bradley proposes might be achieved in a way consistent with the Constitution. We would have to revert to 18th Century law, and in the process throw away many 19th and 20th century laws and precedents. However, common sense is not incompatible with the Constitution. The founding fathers were not ignorant of the responsibilities associated with the right to keep and bear arms.
There are three clauses in the Constitution most directly addressing the gun control issue. These are
United States Constitution, The Bill of Rights, The Second Amendment
A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed.
United States Constitution, Section 8. The Congress shall have Power
Clause 15: To provide for calling forth the Militia to execute the Laws of the Union, suppress Insurrections and repel Invasions;
Clause 16: To provide for organizing, arming, and disciplining, the Militia, and for governing such Part of them as may be employed in the Service of the United States, reserving to the States respectively, the Appointment of the Officers, and the Authority of training the Militia according to the discipline prescribed by Congress;
Who currently is the militia?
US Code Section 311. Militia: composition and classes
(a) The militia of the United States consists of all able-bodied males at least 17 years of age and, except as provided in section 313 of title 32, under 45 years of age who are, or who have made a declaration of intention to become, citizens of the United States and of female citizens of the United States who are commissioned officers of the National Guard.
(b) The classes of the militia are-- (1) the organized militia, which consists of the National Guard and the Naval Militia; and (2) the unorganized militia, which consists of the members of the militia who are not members of the National Guard or the Naval Militia.
However, the definition of "who is the militia" may be changed by Congress with a simple majority. Altering the Second Amendment and/or section 8 clauses 15 and 16 would require a constitutional amendment. As the nation is very much split on this issue, an amendment is very unlikely.
As I read the above, the Congress could specify mandatory training and doctrine for all members of the militia. Congress could include women in the militia. Congress could include gun safety training and gun storage requirements as part of militia doctrine. Congress should be able to declare that as the threat of insurrection and invasion is currently low, mandatory training of the entire population is not at this time required. Any who wish to temporarily waive the right to bear arms may be exempted from military militia duty and training in the use of arms. Congress might be able to specify some set of weapons that are entirely valid militia weapons. So long as this set of permissible militia weapons is entirely sufficient to enforce laws, suppress insurrections and repel invasions, such a limitation on what weapons may be carried is likely to stand Supreme Court scrutiny.
This does twist the intent of the founding fathers. Originally, there were to be few if any armed employees of the state. The militia - the able bodied males - would enforce the laws, suppress insurrections and repel invasions. The rest of the population - the women and elders - could not be actively called out to fight, but still retained the right to keep and bear arms. When the men marched off to interact with Native American political activists, pursuing political ends by other means, no one questioned that the woman of the house could and should be armed.
The new interpretation would slide the above categories. These days, for the most part, paid professionals should and do enforce the laws, suppress insurrections and repel invasions. The milita would be redefined to be those who stay at home, but still have a right to keep and bear arms in self-defense. The difference is that these days, it might be deemed proper and prudent to train those who stay at home, to teach gun safety, to instruct in rules of engagement, and to enforce some discipline in how weapons are stored. The gun control advocates, under this interpretation, gain a clear legal authority to organize and discipline the armed citizens. The Second Amendment advocates get a direct tie between Congress's power to organize and discipline armed citizens and the right to keep and bear arms.
It might be explicitly stated that convicted felons are excluded from the militia. As by 20th Century doctrine federal law and federal courts can prevent the states from infringing on the Bill of Rights, the states can be prevented from passing and enforcing laws preventing militia members from keeping and bearing arms deemed suitable to militia use. As assault rifles are the modern infantry weapon of choice for repelling invasions, it is plausible that a challenge to assault weapons being declared not suitable for militia use might be pushed through the courts. However, such a challenge to current assault weapons bans has long been possible, and no one has tried to push the issue. As the states and gun control advocates are accustomed to 19th Century precedents authorizing state and local gun control laws, if the Congress attempted to use its power to arm, organize and discipline the militia, someone would likely take it to court. However, the language of the Constitution and the wording of various extant Supreme Court precedents make such challenges fragile. The Second Amendment Supreme Court cases commonly include mention that if the federal government calls upon the militia, the states may do nothing to block the call.
While Congress has the power to set nation wide militia doctrine, it is up to the states to implement training and assign officers. (This was a hard fought compromise between those who wished all militia trained to a common doctrine and those who wished the militia to be an effective check to the power of the central government.) If a state chooses not to implement training and assign officers, they should not infringe on the right to bear arms and may not interfere with citizens making a good faith effort to abide by congressional militia doctrine. Congress should set a doctrine that is complete but not complex. It must be understandable by all. Any doctrines related to use of arms must be executable and sensible to an average citizen in time of crisis. When the time comes to defend self or community, the rules of engagement have to be clear and simple. Congress must not leave room for states to set up complex and impossible tests for militia membership, tests that could lead to deliberate efforts by the state to exclude individuals or groups from militia membership. Congress should not allow states to make militia training sessions so frequent or so hard to reach that maintaining one's right to keep and bears arms becomes an undue burden.
Congress should also specify that membership in the militia may not be denied due to religion, race, political affiliation, gender, sexual preference, etc Members must be of voting age, be US citizens, or have applied for US citizenship. Congress should specify that any waiver of the right to bear arms be temporary. A qualified individual who wishes to revoke the waiver, is willing to resume militia training, must have a rapid path to restore his or her full Second Amendment rights.
The above is closer to a true compromise. Both the gun control and Second Amendment factions get much of what they want. Alas, both sides would also lose something they had. Both sides would squawk loudly. My own concern is more for maintaining rule of law than for either keeping guns unregulated or regulating guns. Thus, I would start with the Congress's enumerated powers in the Constitution and work from there. However, gun control advocates are not likely to wish the Congress to firmly reestablish and enforce the Second Amendment. Some gun owners are not apt to agree to reestablishing militia training and discipline. Thus, the stand off between the extremists is apt to continue. Abiding by the Constitution is a valid option, not inconsistent with common sense, but can a majority of Congress be swayed to this path?