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Ever since Donald Trump effectively won the Republican presidential nomination by decisively defeating Ted Cruz in the Indiana primary, Congressional Republicans led by House Speaker Paul Ryan and Senate Majority Leader Mitch McConnell have engaged in unseemly public hand-wringing about whether they will or will not accept the people's choice. Unwilling to support the positions that Trump campaigned on -- reducing immigration, adopting a pro-American trade policy, and returning education to the local level -- Speaker Ryan dusted off his own policy agenda and promised to roll out a series of position papers to compete with those of the presumptive nominee.

One of Ryan's six task forces, entitled Restoring Constitutional Authority, announced its purpose to "Reclaim power ceded to the executive branch by ... exercising the power of the purse and conducting more robust oversight." That's a worthy goal, and the annual defense bill (known as NDAA) now moving through Congress is a great opportunity for Congress to reclaim its power to limit the use of women in the armed forces.

Unknown to most Americans, the Obama administration unilaterally decided to make military women eligible for assignment to ground combat units in the infantry and special forces. Our nation has never allowed the assignment of women to units whose mission is to seek out, engage and kill the enemy, and no other country (not even Israel) does so today.

Although women have not yet been assigned to Special Forces and combat infantry, the official change in policy has already raised the risks for military women who serve honorably in non-combat roles. It has opened the door for women to be drafted into service as combat troops in a future war.

From 1940 to 1973, the Selective Service System drafted young men into the armed forces; that's how we got combat troops for World War II, Korea and Vietnam. Since 1980, all young men age 18-26 have been required to register with Selective Service for a potential future draft, and those who fail to register are disqualified from federal student loans.

Everyone knows that the president is the commander-in-chief of America's armed forces. But our Constitution gives Congress the power "to raise and support armies;" "to provide and maintain a navy;" and "to make rules for the government and regulation of the land and naval forces."

Congress has no more important responsibility than to prevent the compulsory assignment of women to military combat, and there's no better reason why grassroots Republicans are frustrated with this Republican Congress than its failure to do so. Despite the "robust oversight" promised by Speaker Ryan, Congress has not held a single hearing on this radical change in policy about women in the military.

The failure continued last month in the House Armed Services Committee, where a draft-our-daughters provision was attached to the annual defense authorization bill with the support of 6 of the 36 Republicans on that committee. Only a procedural maneuver by the House Rules Committee was able to strip out the provision before NDAA passed the full House.

When the Senate Armed Services Committee took up its version of the NDAA, the chairman, John McCain, exercised his prerogative to add a draft-our-daughters provision to the bill. A motion by Senator Mike Lee (R-UT) to strike that provision was defeated when 6 Republican Senators joined all the committee's Democrats to support the registration of women for military service.

There's no Rules Committee in the Senate, which requires unanimous consent for most action, and Democrats refused to allow Mike Lee's amendment to be considered on the floor. As a result, a "No" vote on the entire NDAA is the only way to prevent the draft-our-daughters law from passing the full Senate.

The 2012 platform of the Republican Party declares categorically: "We support military women's exemption from direct ground combat units and infantry battalions." The platform also states: "We reject the use of the military as a platform for social experimentation and will not accept attempts to undermine military priorities and mission readiness." This year's Republican platform committee will convene on July 11 in Cleveland.

Military combat units draw their strength from "unit cohesion," not diversity. The U.S. Marine Corps' gender integration study, which is the most comprehensive research ever conducted on this issue, reported last September that all-male combat teams outperformed mixed-gender teams on a wide variety of measures of speed, endurance, lethality, negotiating obstacles, and evacuation of casualties.

The female Marines studied were physically fit, but they nevertheless experienced injuries at twice the rate of male Marines. Combat troops fight in small teams where the loss of one member can be fatal to all.

Relying on its study proving that mixed-gender units are less effective, the Marine Corps requested permission to keep some combat roles male-only. Obama's Secretary of Defense not only denied that reasonable request, but ordered the Corps to require Marines to undergo training to erase "unconscious bias" and clamp down on potential misgivings about women in combat.