Legal aliens seeking to become citizens don't have to pledge to  “bear arms on behalf of the United States." anymore, thanks to a ruling by the US Citizenship and Immigration Service (USCIS). In fact, they don't even have to list a religious objection to serving in the armed forces.

Breitbart:

According to the Naturalization Fact Sheet on the US Citizenship and Immigration Service (USCIS) website, In the fiscal year ending June 30, 2015, the nation welcomed 729,995 Legal Permanent Residents into full citizenship.

• Over the past decade 6.6 million have been naturalized through a process that ends with the Oath of Allegiance.
• In the decade 1980-1990, the average number completing Naturalization was only 220,000 annually, but from 1990 to 2000 that number jumped to over 500,000  annually.
• 1,050,399  new citizens were welcomed in the year 2008.
• 18.7 million immigrants are eligible to eventually become citizens, and 8.8 million already meet the 5-year residency requirement.

The pledge to help defend America was good enough for the 6.6 million immigrants naturalized since 2005 and good enough for the over 15 million naturalized since 1980, but Obama’s appointees at the USCIS think that is too much to ask of the 18.7 million estimated legal immigrants eligible today for eventual naturalization or the 750,000 who will be naturalized in the coming year.

This radical change was announced a year ago, in July of 2015. Congress did not enact the change in new legislation. There was no congressional debate, no filibuster in the US Senate, and no sit-in in the House to demand that a bill to repeal the USCIS action be brought to a vote.

No, this radical change was implemented while Congress slept. Like other Obama actions to undermine our immigration laws, the Republican-controlled Congress has not used its constitutional powers to reverse the administrative action. Thank God many states are stepping up to fill that void.

Once again, Obama is abusing his broad authority to enforce the law by allowing naturalized citizens to opt out of pledging to take up arms to defend the US.  The executive branch's authority to interpret the law is limited - by tradition anyway - to remaining true to the intent of Congress. Obama has turned this concept on its head to the point that the will of Congress is ignored in favor of executive decrees. 

Former Rep. Tancredo, the author of this piece, believes that Congress has a magic wand that it can wave to make these executive orders go away. In fact, any legislative action to reverse this policy would immediately end up in court, where rulings almost always favor the broad interpretation of presidential authority. The immigration orders have been defeated because the overreach by the president was so egregious. But allowing new citizens to opt out of serving in the military isn't anywhere near that threshold.

Congress could sue the executive branch, but the question of standing in this case is iffy. In short, Obama gets his way because he's willing to violate tradition and the Constitution itself to achieve his policy goals.